MATING & GENDERS
It isn't always easy to tell sexes apart unless you can carefully examine the tarantula using a powerful hand lens. Immature males look much the same as females, while mature specimens of either sex are broadly similar. Generally, the wild-caught tarantulas you will see in pet shops are males because these are so much easier to catch in the wild when they are looking for a mate.
If you are about to purchase your first tarantula, it is unlikely that
you will be thinking about breeding in the immediate future. Actually,
it is best to gain some practical experience with these animals before
you embark on what is a much more involved aspect of the hobby.
The actual act of copulation in spiders is generally quite rapid, this being a desirable need in a species where the female just might eat her mate given half the chance! An average time would be no longer than 30 seconds, though much longer pairings have been observed. Assuming the mating was successful, the female will develop the eggs over a period of five to ten weeks (depending on the species), at which time she will spin a silken web on which the tiny eggs will be laid. In numbers, there can be anything from 50-700 eggs, again depending on the species. Where a large number are laid you can assume that in the wild the mortality rate will be very high, arising from a mixture of infertility, predating, diseased eggs, and cannibalism.
Under captive conditions a much larger number of the offspring can be raised to maturity if husbandry techniques are adequate. This can prove a mixed blessing. Once the eggs are laid the female will carefully wrap these up in silk so that a ball is created. In this the eggs will be incubated for one to four months. During this period the female will rarely stray far from her offspring.
Once the eggs hatch the little spiderlings will quickly scuttle off to seek shelter. If they hang around too long their mother will commence dining upon them! While the spiderlings are still in their silken cocoon they will hatch and experience their first molt. Once they leave the silk ball they will molt again about a week later and repeat the process as they grow. For this part, the male tarantula on maturing will spin a special web on which he deposits his sperm. He will then alight on the web and, using his pedipalps, will draw the sperm into the special mating structures on the tarsal portion of the pedipalps. The tip of this special structure is called the embolus, and it is this that the male inserts into one of the genital openings of the female.
If you decide to mate your tarantula always introduce the male into the
female's terrarium, never the other way around as is normal with most
pet mammal species.
Rearing the youngsters:
the eggs have hatched through a small aperture that appears in the egg
sack the female should be removed to a new home so the youngsters can
grow in safety. The baby spiders can be supplied with a pile of moss,
and in this and the substrate they will live for a few weeks with no problems.
Of course, the larger and stronger ones will eat the weaklings, but this
natures way and there is little we can do about it at this stage. Some
fruit flies can be placed in the terrarium on a regular basis to provide
food for the growing spiders. After a few weeks it will be time to separate
the youngsters, otherwise the death rate will start to rise rather sharply.
This is when the hard work really begins, because you may still have 100
or more babies (maybe up to 400!) Each now needing their own home! A stock
of small jars with gauze covered lids will be fine, but any sealed container
you can obtain in quantity will be satisfactory. This should be half filled
with potting soil and little moss or cotton wool that will hold the needed
moisture. The babies will need to be fed at least twice a week and with
a couple of hundred or more youngsters this becomes a major chore. Microcrickets
(pinheads) can also be part of the diet as the little spiders get larger
with each molt.