Breeding spiders
(using the example of tarantulas)

 

Previous successful projects

 

(since 2021; we already had our first successful mating in the late 90s with Tliltocatl vagans (then still known as Brachypelma).

02.2021 - Tegenaria domestica

05.2021 - Theraphosinae sp. piura (Thrixopelma pruriens)

05.2021 - Chilobrachys kaeng krachan

08.2021 - Lycosa tarantula

09.2021 - Neoholothele incei (male gold, female classic)

10.2021 - Psalmopoeus langenbucheri

11.2021 - Pterinochilus murinus (rcf)

12.2021 - Hogna schmitzi

01.2022 - Idiothele mira

...

 

The Art of Spider Breeding...

 

...which is actually not art at all!

It should be said in advance: "many roads lead to Rome", so there are also many methods of successfully mating spiders. I make no claim to perfection with the following lines, I just show how it leads to success for us and hope that some readers will find further information included!

Of course, there are certain framework conditions to be observed when reproducing spiders, but it usually works as follows:

male to female (both adult) - mating - male is eaten or escapes - time elapses until an egg sac is built by the female - small spiders scurry through enclosures...

However, there are also types that require a certain knowledge and more demanding conditions. For example, with Grammostola pulchra it is necessary to plan a hibernation so that the animal is encouraged to produce an egg sac later. Still other species require a simulated rainy season to ensure successful reproduction. But let's start at the beginning.

 

Mating

 

In order for spiders to mate successfully, both the female and male individuals must be adult, i.e. sexually mature. For the male, the mature moult is also the last. After its last segment of the pedipalps (left and right of the chelicerae) are fully formed, it has relatively little time to find a suitable female. Females usually live much longer (there are exceptions here too, for example there are species in which the mother animal serves as food for the offspring) and - in the example of tarantulas - still have many years to live after their mature moult. But we don't want to get too deep into the subject here.

If you now have two adult animals of the same species, you should ensure that the female is fed sufficiently, as otherwise the risk of the male being eaten after mating increases. In nature, this is a relatively logical process. By eating her partner, the expectant mother covers the necessary nutrients to build a resource-demanding egg sack. With our method, we do not intervene in what is happening. So we don't stand ready with tweezers (which can definitely disturb the animals!) to intervene if necessary, either the male escapes or not. If you now have a well fed female, you should also keep an eye on the male. This should have produced a sperm net in the fore field in order to fill its bulbs with sperm. Then he is ready too. Now the male animal is placed in the female's enclosure. If possible quiet and with time, without disturbing or scaring the animals too much. A proven method is to open the fronts of both terrariums and place them next to each other. In this way, the animals can get closer to each other - as they please. As soon as the male senses the presence of the female (usually through pheromones on the female's web), he will start drumming. What follows may vary depending on the species. Males either put the pedipalps back on the ground twitching, or they also use their 8 legs to "knock"​ (species such as Chilobrachys kaeng krachen - video on the left / below - raise their pedipalps and rapidly wave back and forth, for example). When the Female Spider is ready, she will respond appropriately with drumming motions. They're slowly getting closer. Depending on the species, this can take minutes or several hours.

In the further course, another sexual characteristic of the males is used. On both front legs it has a so-called tibia hook (there are exceptions here too!), with which it can push the female front body backwards in order to reach the female spermatheca with its bulbs. There he can then deposit his reproductive substance and the actual mating is over. Since the male is now mostly below the female, hurry is the order of the day. The male will flee after successful fertilization or be eaten on the spot. If the act was successful, the female will start building an egg sac in the foreseeable future.

 

...until they hatch

 

After successful mating, the female continues to be well fed to support egg laying. The period of mating varies greatly and depends on various factors (species, housing conditions, etc.). It can take up to six months until the eggs are laid and an egg sac is produced. But there are also spiders that start after just a few weeks. If circumstances permit, the female, who continues to store sperm in her spermatheca, will withdraw and weave shut the entrance to her dwelling. In the shelter of her cave, she now spins a kind of carpet on which she lays her eggs, which are then fertilized. Approximately another two months pass before the eggs slowly develop into larvae in the cocoon. During this time there are species that always carry the egg sac with them and also rotate it so that individual eggs do not start to rot. Other species, on the other hand, fix the egg sac in a fixed place in the hiding place. During this time, the animals should not be disturbed unnecessarily, as females usually do not eat until the offspring hatch. It is enough to provide water.

Whether you leave the egg sac with the mother or remove it early is up to you. We handle this differently. If a good opportunity presents itself and enough time has passed that we can assume that there are already eggs-with-leggs in the cocoon, then we carefully try to remove the egg sac with tweezers. Experience is an advantage here, the mother will defend her egg sac. If you have successfully stolen the cocoon, you open it and put the larvae or eggs that have not yet formed in an incubator. You can build this yourself or use an electronically adjustable device. For the do-it-yourself variant you need a plastic box with a lid in which you make a few ventilation holes and fill the bottom with some vermiculite. Now add water to it. In this box you now put a second, smaller box (lined with cellulose and lid with ventilation). Place the eggs on the cellulose and ensure that the large box does not dry out, but also that no water gets to the eggs / larvae. But there are also inexpensive incubators with temperature control. This is a clear advantage, especially in the cold months.
But you can also leave the egg sac in the mother's enclosure and let nature take its course. Good results can be obtained with all methods. There are also breeders who remove the egg sac as soon as they see it and then place it in the incubator. That is also possible. Everyone has to find the best method for themselves.

Spider larva (egg-with-legs).

Eggs-with-legs (Thrixopelma pruriens).

In this male (Caribena versicolor) a palpal bulb (on the front part of the pedipalps) is clearly visible.

The behavior of a male Chilobrachys kaeng krachan during mating.

Spiderlings N1/N2

An electric incubator with temperature control (left) and a homemade incubator (right). Both methods lead to success.

The first enclosure after separating. A tag can be beneficial depending on how many species you breed.

Thrixopelma pruriens N1

 

...after hatching

 

Depending on the method described above, the larvae are left in the care of the mother and the incubator is checked regularly. After some time, the offspring would have reached a stage where they are still relatively small, but already fully hairy and clearly colored. Now you have a Spiderling in front of you, which will eat independently, i.e. hunt. So far, the little ones have been feeding on the egg yolk supply. Now at the latest you should also separate the animals from their mothers. To do this, we fill a small box with soil (again with sufficient ventilation) and separate each animal into one of these enclosures. Depending on the species (the size of the spidelings can also vary greatly - as with the adult animals) fruit flies or freshly hatched crickets are fed (once or twice a week). Young spiders in particular can dry out quickly, so you should keep the soil slightly moist. One should always be prepared, species like Lasiodora can yield well over 1000 eggs in an egg sac. Accordingly, cans, soil and feed must also be available. It can also take several hours a week until the little ones are taken care of. You should also know in advance where you are going. What happens to the animals now? If you don't take care of buyers in time, you'll soon have more legs than you can handle. Of course, one could go much, much deeper into the subject here, but this should at least give a certain overview of how it is generally with the breeding of spiders. If you have any questions on the subject, please do not hesitate to contact us via "Contact".

Avicularia purpurea N2