Why Is My Tarantula Climbing the Walls?

Every new keeper has a moment when they wonder why their tarantula is doing something that they don’t think it should. For example, why would a terrestrial tarantula start climbing the walls? To find the answer, you have to look at the setup and see if you’re meeting the needs of the spider.

There are multiple reasons why a tarantula with terrestrial habits may start pacing the enclosure or hanging out on the walls. Often, it is related to issues with the substrate. For example, a tarantula may leave the ground if the substrate is too wet or it has a fungus growing in it, which can easily happen if the enclosure isn’t well ventilated. Newly transferred tarantulas tend to pace, and so do mature males when they’re ready to mate. The spider may also be hungry or looking for water.

Why is my new tarantula spending all its time on the walls?

There are a variety of reasons why tarantulas leave their burrows or webs to pace when we’re keeping them in captivity.

These reasons can include looking for food and water, needing better anchor points for webbing, seeking out a mate, looking for a better place to hide, or being restless because they were recently rehoused. The enclosure size can also influence a tarantula’s behavior.

One quick thing to check if you’re wondering if your tarantula is merely hungry is the size of the abdomen. If it’s still plump, then this is unlikely to be the reason behind why the spider is wandering.

Tarantulas that have recently been moved to a new enclosure tend to act restlessly for a period of time. This seems to happen more with spiders that aren’t given a starter burrow or another place to hide.

When you provide a starter burrow, the newly transferred tarantula will often bolt straight into it and stay there until they feel comfortable enough to start customizing the enclosure to their liking.

If the tarantula doesn’t settle down within a couple of weeks, then take a look at the enclosure. Do you have it set up in a way that the spider would feel secure?

For example, bare enclosures are a common theme I see on Arachnoboards when people transfer their arboreal slings.

Make sure the tarantula has an adequate level of substrate, a piece of cork bark or another suitable hide, and provide enough anchor points for arboreals to start webbing by adding foliage or sticks.

Sometimes new keepers make the mistake of using a heat lamp for their tarantulas which will definitely make them pace restlessly either because they can’t get away from the heat or they dislike the constant light.

Make sure you are aren’t doing this. Remember, it’s a spider, not a reptile, and as long as you’re comfortable in the room the tarantula will be fine also.

Why won’t my tarantula stay on the substrate?

Usually when a tarantula is reluctant to stay in one place on the ground the substrate is too wet, although sometimes this can indicate that the substrate is too dry. Some tarantulas are more moisture dependent than others.

Soggy substrate is prevented by ensuring there are adequate ventilation holes for proper airflow, and always taking the time to allow the substrate to dry out before adding it to the tank if it’s a type that you had to rehydrate from a brick.

Alternatively, sometimes a live feeder may be bothering it. If your tarantula doesn’t eat everything that you offer, make sure you take the prey back out.

Aside from stressing the spider to the point of climbing the walls, a live feeder is also potentially dangerous to a molting tarantula.

The type of substrate being used can also cause a tarantula to become restless. Make sure you are offering it something meant for arachnids.

Suitable tarantula substrates include coconut coir, peat moss, premium soil mixtures like Terra Aranea, and DIY substrate mixes that you find on arachnid keeping forums. Don’t keep tarantulas on wood chips, sand, paper towels, or gravel.

Why is my tarantula suddenly pacing the enclosure constantly?

Sometimes tarantulas will pace when they’re looking for something to drink. They will also come out more frequently if the enclosure is too small because there’s nowhere else for them to go. Or, they may pace because the enclosure is too large and void of any suitable hiding places.

If there aren’t any husbandry issues at play, then it’s possible that the tarantula molted into a mature male. If you didn’t sex one of the molts as the spider grew, then you aren’t going to be left guessing.

Once a male has reached its ultimate molt they display physical differences from the females. You will find bulbous pedipalps on all mature males, and many species will hook out. This means that the males develop tibial hooks on their front legs.

Males are rarely at rest in their enclosures and will roam seemingly endlessly in their search for a female. Occasionally, adult females will also pace their enclosures and drum indicating that they are looking for a mate. However, that isn’t nearly as common.

If you have no intention of breeding, then you may want to consider moving the male to a smaller enclosure to reduce his stress and prevent any injuries from his constant pacing.

How do I dry out the substrate in my tarantula enclosure?

If you have adequate ventilation in your enclosure, but you happened to overwater the substrate, then all you need to do is wait for it to dry out.

You do not need to take out the substrate and bother the spider. The tarantula will be fine in the meantime, and now you know what not to do in the future. You can tell when the substrate is starting to dry because it will become lighter in color.

However, if your substrate is taking a long time to dry, then check to make sure you have enough cross ventilation in the enclosure. Cross ventilation means that there are holes drilled on two parallel sides of the enclosure so that air can pass freely. I tend to set up my enclosures so that there is ventilation near the surface of the substrate.

If there isn’t adequate ventilation, then the container is at high risk of becoming stagnant or growing mold and other types of fungi. You may need to remove the tarantula so you can add more holes for airflow, and replace the substrate or physically dry out the wet substrate using heat before it is placed back in the enclosure.

Keep in mind that the way you regulate substrate moisture is going to depend on where you’re located. My method for keeping the lower levels of the soil moist here in Arizona is likely to vary drastically from someone located in a more humid environment.

How do I get my tarantula to stop hanging on the lid?

If you’re keeping a terrestrial species and the tarantula is climbing up to the top of the enclosure because something is wrong with their environment, then you will first need to correct any husbandry mistakes.

Once you’ve fixed the problem all you can do is wait. Eventually, the tarantula will come back down and settle in.

Common husbandry mistakes include substrate that’s too soggy, an unchecked outbreak of fungi (like mold or mushrooms), and live food left inside of the enclosure.

Another common reason why terrestrial T’s take to the lid is a change in the substrate type. If the spider hasn’t come back down and settled in within a couple of weeks, then it may not like walking on its new substrate.

Keep in mind that it is completely normal for arboreal tarantulas to hang out at the top of the enclosure. If you’re concerned about ruining their web each time you open the lid, then consider placing the cork bark and other anchor points so that there is a slight gap between the lid and the decorations.

This will often encourage arboreals to make their webs lower, however, just know it doesn’t always work.

How can I tell if my tarantula is stressed or acting normally?

Aside from pacing, a stressed tarantula will often sit with their legs scrunched up over their eyes. Alternatively, they sometimes get more defensive than usual.

New World species that have urticating hairs will kick their hair until the abdomen is bald when they’re extremely stressed.

As a side note, hair kicking is not always a sign of stress. Tarantulas that have them will lay down a patch of urticating hairs, either on the substrate or their webbing, prior to molting as protection from predators.

The picture below shows a stressed Chromatopelma cyaneopubescens during a rehouse. Notice how she’s pulling her legs over her carapace trying to look as small as possible?

How can I prevent my tarantula from getting hurt when it climbs?

It’s important to make sure that the substrate is deep enough to prevent terrestrial tarantulas from getting hurt if they fall when they’re climbing. The necessary depth of the substrate depends on how large of an enclosure you’re using, and also on the size of the tarantula.

A general rule of thumb to follow for terrestrials is to make sure that the substrate level is tall enough so that the tarantula can reach the lid with its leg span, even for species that don’t like to burrow much.

Keeping the substrate deep like this not only gives them the option to create a hole, but it prevents any fatal falls where the tarantula damages its abdomen.

Keeping the substrate level too low is a common mistake that new keepers make, and you’ll often see people saying enclosures need more substrate on tarantula forums.

If your terrestrial tanks don’t look like you’re keeping a container of dirt, then you’re probably not using enough. It’s also best to avoid screen lids, especially for terrestrial tarantulas. They have a habit of getting their little toe claws stuck in the mesh.

If you currently have a screen lid on the enclosure of a tarantula that climbs to the lid often, then you may want to consider replacing it with a piece of acrylic modified to fit the tank.

Is it normal for a tarantula to sometimes get up and walk laps around the container?

Although terrestrial tarantulas are often likened to pet holes, they are not always stationary and they do come out a fair bit to explore the enclosure.

Coming out to walk around from time to time is completely normal behavior, especially if the lights were recently turned off. If your tarantula hangs out in its burrow for the majority of the day coming out briefly for a stroll there isn’t anything to worry about.

Final Thoughts on Tarantulas Pacing

Provided that you aren’t dealing with a brand-new spider, if a tarantula is climbing the walls of its enclosure, or constantly hanging from the lid, then you need to look closer at your setup. New tarantulas can take weeks to settle into their new home, and mature male tarantulas will restlessly pace no matter what you do. If you’ve given the tarantula enough time to settle in, make sure you check that your enclosure has the proper type of substrate and a suitable hide for the spider to use.