Questions related to the molting process, also known as ecdysis, are commonly posted on message boards by panicked keepers. It can be startling to see a tarantula turned onto its back for the first time, and many people new to the hobby wonder if they are dead.
Tarantulas kept in captivity do sometimes die during molting. Whether or not they have success during the process is largely influenced by their internal hydration. It’s imperative that you do not disturb a tarantula that is molting because it may stop altogether and get stuck. Typically, they will molt flipped over on their backs as opposed to right side up.
Why do tarantulas die during molting?
Hobbyists don’t have a clear answer as to why tarantulas get stuck in their old exoskeleton while they are in the molting process, but there are many suspected things that can cause this to happen in captivity.
In the wild, a spider going through ecdysis is vulnerable to predation and desiccation.
One of the most common reasons why keepers speculate that their T’s get stuck in molts is related to inadequate internal hydration or a lack of moisture in the enclosure before the process.
When a tarantula molts, it loses a lot of moisture during the process which is why it’s important to offer them water to drink during the weeks (or months) that they are in premolt and also after they finish hardening.
Stress is a possible reason for failed molts. There are a variety of factors that can stress a molting tarantula, like intentionally touching it, blowing on it, keeping a heat lamp on it, or leaving live feeders in the cage with it. Sometimes older specimens are just too weak to pull themselves out of their old exoskeleton successfully.
Is my tarantula dying or molting?
While there are occasional exceptions, a tarantula will almost always molt flipped onto its back with its legs curled on top of it. This is different from the way that they curl their legs underneath them while standing upright when they go into a death curl.
If you’re worried that your tarantula has died during its molt, then give it at least 24-48 hours before you call it a loss. Freshly molted tarantulas will often sit motionless for long periods of time while their exoskeleton is hardening.
Do tarantulas practice molting?
Occasionally keepers will observe their tarantulas flipping on their backs, staying that way for several hours, then flipping back over and continuing on as normal. This may even happen several times in a row. This does not mean that the spider is practicing for a molt.
It indicates that something may be wrong and that the spider is unable to initiate the molting process. For example, they may be too weak or dehydrated to pop the carapace. Specimens that exhibit this behavior may not successfully complete their molt when they finally do start.
Sometimes a tarantula will flip back over after being on its back because it was disturbed before it could start the process. In these instances, the spider usually returns to the correct position in short order and completes the molt.
Is it okay if my tarantula sealed its burrow while it molts?
Sealing the entrance of their tunnel or web tube is a very common behavior for tarantulas prior to molting. Not only do terrestrial and arboreal specimens in captivity do this, but so do tarantulas in the wild. This is effectively their way of hanging a do not disturb sign on their door.
Not all tarantulas will create a barricade prior to starting. Some will molt out in the open in their enclosure or underneath a hide that you can look inside to watch the process.
When they molt out in the open you will often see the spider laying down a molting mat, which is a thick layer of webbing that they will flip over on top of.
Can you help a tarantula molt?
The best thing that you can do when you notice that one of your spiders is in premolt is to keep fresh water available to it at all times. You can tell that a tarantula is in premolt because it will become more sluggish, it will refuse to eat, and its color will become duller or darker looking.
Some keepers do choose to help their tarantulas if it appears that the specimen has been in the molting position too long with no signs of progression after the carapace has already been popped open.
One clear sign that a tarantula is having trouble molting is if they are pulling themselves out of the old exoskeleton asymmetrically.
If it is absolutely clear without a doubt that the specimen is not going successfully molt on their own, then a keeper may decide to help them using soft tools, such as paintbrushes or Q-tips, that have been moistened with water.
Should I remove the molt after my tarantula finishes?
If you can easily access the molt after the spider finishes then you should remove it once the tarantula has been given time to harden again. Molts can be used to determine the sex of the specimen if they are intact enough.
However, if it isn’t easy to pick out with tongs, then just leave it in the enclosure. Don’t destroy a burrow or pull down any webbing in an effort to remove it.
Tarantulas are surprisingly good at doing their own housekeeping, and you’ll more than likely find it tossed out into a “trash” pile or in the water dish soon.
Leaving molts in the cage will not hurt the spider, but exuviae will add to the clutter if there’s already a lot of webbing.
Do tarantulas eat their molt?
A tarantula does not eat the old exuvia, however, it is common for them to appear to be eating it after a molt. What they are actually doing is attempting to recover some of the moisture that is present on the discarded exoskeleton.
This is what hobbyists are referring to when they say that a tarantula shredded or chewed its molt up so badly that they can’t determine the sex.
Can a tarantula molt right side up?
A tarantula can molt while they are standing upright, and in other odd positions, but it is rare for them to attempt doing this. Most of the time they will flip onto their backs before they molt.
If your tarantula is trying to molt with its legs curled under it, then do not touch it or otherwise try to get it to flip over. Most of the time, upright molts turn out just fine and you are at more risk of doing harm if you try to intervene.
What happens if you disturb a tarantula while it’s molting?
External stimuli can cause a tarantula to stop molting when they first get started, and hobbyists suspect that it can also cause them to get stuck in the molt if they have already started the process.
They only time that it is recommended to disturb the enclosure is if you notice a live feeder in with the molting tarantula.
This is because freshly molted spiders are very soft and a live feeder can easily damage or kill them. Do not touch the tarantula if you have to remove a feeder. You can avoid a situation like this by promptly removing unwanted prey items after 24 hours.
Why is my tarantula in a weird position after molting?
Keep in mind that molting is very strenuous for the spider. They can lose a lot of moisture during the process (which is a great reason to keep a water bowl in the enclosure), and they need a period of rest afterward to recover.
It is not uncommon to find newly molted tarantulas lying next to or even on top of their molt with their legs curled up. Do not disturb them at this time because their exoskeleton has not had a chance to harden again.
Tarantulas will also commonly do what I like to call post-molt yoga, which can last all the way up to a week or so after a molt for larger specimens.
They will position themselves into some really awkward looking poses that you don’t seem them doing at any other time.
The stretching can be as simple as spreading their legs out as far as they can go so that the spider is flat on the substrate, to really odd-looking stretches where the tarantula hangs from just a leg or two off their hide.
Final Thoughts on Tarantulas Dying During Molting
Unfortunately, getting stuck in molts happens, especially if you’re caring for an aging specimen. However, you can be proactive in your tarantula’s care by always making sure they are well hydrated as soon as you notice that they are in premolt (just another great reason to keep a water dish available at all times). Misting a stuck tarantula isn’t going to help it after the fact because they rely on internal hydration to complete a successful molt.