Jumping Spider Moulting

If you are wondering if your jumping spider is moulting, or not sure what to expect when they do, then you're not alone. It can be a confusing and worrying time for all keepers, even experienced keepers like myself. This post will explore what to look out for, what happens and how to give your pet jumping spider the best chance at moulting successfully.

What is moulting?

Moulting is a common in the invert world, and jumping spiders moult to remove their old exoskeleton to reveal another newer one in order to grow. Jumping spiders moult around 9 times in their life, but stop moulting once they mature. During a moult they can regrow missing limbs, repair damage, and replace any sense hairs (used for smelling and detecting vibrations/sounds) they may have lost since their last moult. Their colours and markings can also change after a moult, some spiders change a lot some change a little, or some may look just the same.

Regal jumping spiders will naturally moult every 3 to 4 weeks, but after 7th instar there may be longer gaps between moults.

Over-feeding can bring on a moult sooner, just as under-feeding can stop them from moulting. This doesn't effect their overall life span. To maintain a natural moult progression use the abdomen size to determine when to feed your spider.

There are three stages of a moult: Pre-moult, Moulting, and Post-moult.

Pre-moult:

You may notice your spider ignoring or retreating from their prey. Perhaps they are acting a little more skittish around you also. The biggest clue is when a jumping spider stays in it's web hammock for 48hrs or more. They will move a little in their web; they may peek out, and even come out to drink as they will need extra moisture to help them extract themselves from the old exoskeleton and stretch out the new one. Pre-moult can take as little as a few days to as long as a few weeks.

Pre-moult behaviour:

• Rubbing their legs/itching a lot

• Backing away from/acting afraid of their food

• Their abdomen looking more plump than normal

• Working on their web, making it thicker

• Staying in their hammock for 2 days in a row

What should I do if I think my spider is in pre-moult?

You won't need to offer food, and definitely remove any crickets or mealworms as they are omnivorous, and a soft vulnerable jumping spider makes for easy prey. Flies such as bottle flies and fruit flies can be left in as removing them can be more of a disturbance than leaving them in. can be left in the enclosure as this. Continue to mist the enclosure sides, as close to the hammock as you can, once or twice a day.

If you suspect that your jumping spider is in moult and they look to have emerged from their hammock without moulting, please wait 24 hours before handling or moving them to a new enclosure. It is likely your spider has come out for a drink before heading back to their hammock.

Physical Moult:

At some point while they are hidden away, your jumping spider will move into the physical moult stage. They begin by cracking the back of their old exoskeleton and begin to slowly ease their way out backwards. Their legs will be gathered together and stretched out beneath them. Once they are free of the old exoskeleton they contract into what is commonly known as a death curl, don’t be alarmed as this contraction is entirely normal at this stage and eventually, after a few hours they will swell with fluid and uncurl.

Do I need to do anything if I see my spider moulting?

No, there is nothing you can do for your spider at this point. Do not disturb them as they will be as fragile as wet tissue paper. One wrong move at this time could be deadly for the spider

Post-moult

After moulting, there will be a period of time, from a few days to over a week, where your jumping spider will need to harden up their new exoskeleton. They cannot eat during this time as their mouthparts are still soft. Refrain from offering them food or disturbing them. Continue to mist the enclosure once or twice a day.

Once your jumping spider has hardened fully, they will leave their web hammock and and you can offer them food. They will be very hungry and skinny after using up a large amount of energy going through the moult process, so don't wait to feed them. If they are out and hunting, they are ready for feeding.

The time this all takes is down to the individual spider; it takes as long as it takes. It may be a few days, or a few weeks, or even longer.

Jumping spiders moulting outside of their hammock

This is very rare, and very risky, but some jumping spiders moult outside of their hammock for many reasons such as being disturbed from their hammock, unsettled in a new enclosure or low humidity. Moulting this way comes with an increased risk of injury but they can complete it successfully. If you notice your spider has started to shed their exoskeleton outside of their hammock resist the temptation to intervene or help. It is going to be tricky to gauge when they are hardened enough to be fed or interact with them, as there is no hard and fast timescale when it comes to post moult. Offer small prey like flies, about 24hrs after the moult and watch the spiders reaction. If they avoid the prey, then they are still too soft, try again in 24hrs. Once your spider has eaten, you can handle them again.

Should I remove their old moult?

There is no need to remove the old moult, especially if it is stuck in their hammock. If it can be moved your spider will drag it out of the hammock and drop it. You can then take it from the enclosure.

Moulting issues and Mis-moults:

Because jumping spiders are so fragile during moulting, a lot can go wrong. Here we will look at what can go wrong and if we can help, and what we can do to lessen the chances of a moulting issue.

A jumping spider can emerge from a moult with a damaged limb.

One wrong move from a spider during moulting can cause many issues, one of these is a deformed leg, often pointing the wrong way or unable to be moved/used. In most cases this will not hinder the spiders survival, or ability to hunt. The limb will often self-amputate. Self-amputation is where the nearest joint to the damage constricts to that fluid is no longer circulated, and in time the limb will drop off on it's own, or the spider physically tugs it off. If Damage is often repaired during another moult, unless the spider is mature.

Jumping spiders can lose a limb or pedipalp during moulting

Spiders have 8 legs for a reason, if they lose some they can still hunt and live a normal life. A young jumping spider can re-grow missing limbs during a moult. Sometimes the limb may look a little different from the others. A missing pedipalp may hinder their ability to handle their prey, so if they emerge from moult missing a pedipalp you will need to keep an eye on them to make sure they can manage feeding. If they are having trouble you may need to tweezer feed them, or disable their feeders.

A jumping spider who loses 4 or more legs may be unable to successfully moult again, and eventually pass away. You can only help them feed and check the humidity regularly, while hoping for the best.

Their old moult can become stuck to them

If your jumping spider comes out from their moult with some of their old exoskeleton stuck to them, you may need to give them a hand. You can dampen a cotton tipped bub and moisten the area where the old exoskeleton is stuck to help loosen it. You can also up the humidity in the enclosure to between 80-85%, or move them into a damp kitchen roll lined smaller enclosure (often referred to as an ICU) for a boost of humidity. If the moult does not come away, you may have to let nature take its course. They may loosen it themselves when moving around and cleaning, if attached at a limb they may self amputate the limb, or if it has caused unseen damage, you spider may pass away.

In more serious cases the moult may start to harden while the spider is still trying to extract themselves during the physical moulting stage. This is heart-breaking and often fatal.

A jumping spider can fall from their hammock while moulting.

If you find your spider on the floor of their enclosure after they have moulted, especially if they are in a death curl, do not attempt to move them. There is a chance they survived the fall. If your sider is still curled up after 12hrs and is not moving, then I am afraid they have passed.

How to lessen the chance of your spider having a mis-moult

Although a mis-moult can happen even in the best conditions, there are steps you can take to reduce the odds of it happening to your jumping spider.

When it comes to safe moulting husbandry plays a huge part:

-Misting the enclosure is vital. The spider uses fluid to separate their old exoskeleton from their new and will often drink more than normal before the physical moult happens. Continue to mist the enclosure twice a day, aiming as close to their hammock as possible. Try to mist in the mornings. Jumping spiders are diurnal, meaning they are active during the day, and even with artificial lighting you may find the spider is already tucked itself up for bed when the real sun drops and not had a chance to drink.

- Natural or Bio-Active enclosures are best. These help the humidity of your enclosure stay more constant, especially with the use of substrate and moss. Humidity is very important when it comes to jumping spiders and moulting, and in general for their health and comfort. The softer base option from substrate is also more forgiving if a moulting spider should fall from their hammock. Live plants, soft moss, moist spider soil and cork bark will always be the best option for husbandry. At Arachnamoria I focus on habitat-first husbandry and can attest to mis-moults being incredibly rare. - Correct heating helps prevent the enclosure drying out. A heat mat and separate thermostat will help with humidity without creating dry air. Swing by my post of Jumping Spiders and Heating for more information.

-Hygrometers, used the correct way, are a perfect way to measure humidity is in the enclosure. A hygrometer should be suspended high in the enclosure, away from substrate and decor, with plenty of space for it to measure the humidity in the air of the enclosure. The humidity should be between 70 - 80%, fluctuations are natural and very normal so like the temperature you won't have one steady number.

Young jumping spider next to their moult

Key points to remember:

• Jumping spiders moult every 3 to 4 weeks, but can go longer between as they age.

• The time it takes from pre-moult to post-moult depends on the spider.

• Do not feed or disturb your spider if you suspect they are in an of the three stages of moult.

• Mist twice a day near their hammock.

• Husbandry, humidity and misting are key to a successful moult.

• Feed you jumping spider as soon as they come out from moulting.