Breeding tarantulas can be a very tricky business and a combination of knowledge and luck both play a part in the process. When successful breeding is achieved, however, it can be very rewarding - particularly if the species is endangered. The genus Brachypelma is known to be difficult to breed and when dealing with the species B. smithi you know that you will certainly face a challenge.

This brief synopsis of our experience has been given for information purposes, in the hope that others may benefit and that more successful breedings may follow. Our female was mated in the normal way, with the male being introduced to the female’s quarters and not the other way round. After several “copulations” we felt the time was right to pass the male on and hope that he had done his duty with due diligence.

For some six weeks after mating, we fed the female extra large black crickets, which she took with great enthusiasm. We also gave her a pinkie mouse to vary the nutrient intake for the hard days ahead. On 6 January 2000, the spider was removed from her tank (heated to 72°-75°F) and placed in cooler chambers at 60°-65°F. This cooling down is very necessary as it keeps the male sperm cool and does not destroy it through overheating. This behaviour is known to occur in the wild. It is interesting to note that any food offered was now refused.

Between 20th February and 6th March, we gradually increased the temperature to the original level and she regained her appetite for food. On 17th March she was moved (finally) into a new tank with a large ready-made cork-bark/peat retreat. The substrate we used was peat and we also provided a large dish of water. She roamed the tank for a couple of days, presumable checking her new environment, before settling into her new dwelling. All food was now refused and we believed, from previous knowledge and experience, that she was gravid and was, therefore, fasting in preparation for the next stage of the breeding cycle.vThus far, events had proceeded in line with our successful breeding of the same female in 1998 (see British Tarantula Society Journal Vol. 15 No4). Something different now occurred, however. During the previous breeding the tarantula had entered the burrow to make the egg-sac but this time (on 27th April) she began spinning copious amounts of web in full view of everyone (would-be predators included?) in the exposed corner of the tank! (see plate on page overleaf).

This event began at 8.pm and at 2am she was still laying web so we went off to our bed tired and excited. She was still at it when Carl went to work next morning, but at 11-15am something wonderful occurred and I was privileged to see the spider laying her eggs. There were hundreds of spherical pale yellow eggs in a light yolk, which you can clearly see in the plate on the page overleaf. Note how the abdomen has shrunk, presenting a ghastly sight, somewhat akin to a partially deflated football. Heaven knows what the spider was feeling at this point!

After the egg-laying, which took about ten minutes, the female began spinning silk over the top of them in order to cover them quickly. In the wild this would be the prime time for predation of the eggs as they are at their most vulnerable. This took several hours and throughout the process she took regular breaks from this arduous task. In early evening, the egg-sac was complete and the female gathered it all up into a ball together with particles of the peat substrate (see plate overleaf).

After this tremendous effort the spider was exhausted and seemed to collapse by the sac at one point. For the next few weeks she guarded her precious jewel, quite often resting at the opposite side of the tank. Water and food were offered and both were taken. Note that food was only given at the opposite end of the tank to that which the egg-sac was in, so as not to excite the female into thinking the eggs were being attacked. Additionally, we did not want any mites from cricket remains to be anywhere near the egg-sac.

We removed the sac to complete the incubation on 5th August. This was done because it was due to open any day and we did not wish to “lose” the tiny spiderlings in the brown peat substrate. We gave the female two large crickets to take her mind off the egg-sac and she seemed quite calm about this tactic. In fact, she did not even bother looking for the silk ball once she had finished her meal. This seemed very unusual to us, because even though the spider often spent time at the opposite end of the tank to the egg-sac, she always knew where her offspring were located should she need to be in attendance.

How did we incubate the eggs? Well, we placed the egg-sac in a large plastic container with plenty of small air holes in the lid. The egg-sac was placed on a thick wad of kitchen towel and in one corner of the container we put a damp piece of kitchen towel into milk bottle top to maintain humidity. It was important for this to be damp but not wet. The temperature was maintained at about 70°F.

We turned the egg-sac twice daily, as the mother might do in the wild. This helps to redistribute the weight within the sac and prevent all the eggs settling into a mass at the bottom. We also made a small incision in the wall of the sac to observe the viability of the incumbents and this proved the nymphs were alive and well. After three days the nymphs began to emerge and congregate around the sac (see the plate on the facing page). It is interesting to note that not one of the young moved individually, but all moved in perfect synchronicity – perhaps to confuse any would-be predator.

The colour of the young spiders changed from pink to black over the next few days and they soon moulted to become handsome spiderlings. This moult occurred on 25 August. There were 692 in total, and there were no casualties.

All in all it was a very interesting experience and tremendously satisfying. Little recognition is given to the theraphosid enthusiasts all over the world who breed these endangered animals. If it had been a cuddly or “socially acceptable” animal it would probably have made news headlines somewhere. It goes to show that although we fight every day against the prejudice surrounding spiders, we can (and do) make a tangible difference.

The tarantula is (not) dead…long live the tarantula.