Our seven inch female Grammostola aureostriata (Chaco Golden Knee) had been “pre-molt” for a few weeks now. (The hairless patch on her abdomen turned from pink to black, she stopped eating, etc.) Every time I passed her tank, I looked in, hoping to see her in the process of molting. Finally, on the morning of February 13, I found her like this…
For those of you not familiar with tarantula behaviors, this is actually a good sign. Being invertebrates, tarantulas need to shed their exoskeleton in order to grow. This is called molting. Smaller spiders can do this several times a year (depending on the species), while larger tarantulas, like our Chaco here, usually do this once a year. When they are on their backs, their carapace “pops” open and the spider pushes its old skin off. For our big girl here, she laid on her back for over 15 hours before she began coming out of her old skin! (The picture below is one of the few that came out. We did not want to disturb her by opening the cage for a better picture. If you look carefully, you can see the first signs of her gray/white body pushing off the old skin.)
About 90 minutes later, she was finished. (Thank goodness!) You see, not only is the molting process necessary, but it is also a very dangerous time for the spider. If the tarantula gets stuck inside their old skin, they will die. For those that do make it out safely, they are like Superman holding a bag full of Kryptonite. They are extremely vulnerable at this time, as their exoskeleton is still soft and pliable – as are their fangs. Their energy is spent as well, so they are a moist, eight legged helpless baby for a while. Lucky for the captive tarantulas, there are no predators to come along and take advantage of this situation.
It is now the end of the week, and she is doing better everyday. She is stretching her legs out and moving about the cage every-so-slightly. Her overall color is much darker than it was in premolt, and the gold markings on her skin are vibrant. (Here is the molt itself, still intact after the process.)