Like all arthropods, tarantulas moult on a regular basis. This not only allows them to grow but also replaces not only hairs that may have been lost but also gives tarantulas a chance to regenerate lost body parts such as legs.
Whilst adult tarantulas typically moult only once a year, younger tarantulas will moult far more often with some youngsters moulting every few months.
When your tarantula is coming up to moult it will typically stop feeding for a few weeks so if your spider goes off it’s food this is a good indication that it may be coming up to moult soon.
Furthermore, if your tarantula is a species which has urticating hairs, you may notice the bald patch on it’s abdomen going black as the spider’s outer skin starts to separate from the new skin underneath and fresh hairs begin to grow under the surface.
A few weeks later your tarantula will normally moult and this is one aspect of tarantula care for which some additional effort is required.
Firstly, you should ensure that no livefood is present in the cage which may stress out your tarantula while it is soft and vulnerable. Furthermore some insect prey, such as crickets, may even take advantage of a moulting tarantula and may try to bite it.
Furthermore, most tarantulas require a higher humidity when moulting so if your spider looks like it is getting ready to change it’s skin, take the time to gently spray the inside of the cage, avoiding the spider itself, so that there is more moisture in the air.
Once your tarantula has safely moulted, try to leave it well alone for a few weeks to recover from this traumatic experience. At this point you can remove the skin and try feeding your spider again. After the enforced fasting, many tarantulas will be very hungry after a moult and so should be given as much food as they will take over the next few weeks to help them regain their strength.