Are Ants a Danger to Tarantulas?
If you regularly deal with ants invading your home, then you may be wondering if they are dangerous to your tarantulas.
Ants can easily kill a full-grown tarantula. Although a single ant in unlikely to be a problem, a group of ants poses a serious threat to spiders of all sizes. Ants will enter enclosures to eat leftover food boluses and dead feeder items like crickets and roaches. The best way to prevent ants is to keep the enclosure clean with thorough spot maintenance. Once ants become a problem it is a lot of work to eradicate them.
Can ants cohabitate with a tarantula in captivity?
Unlike in the wild, a tarantula has nowhere to escape if ants get into its burrow in captivity. I have never encountered someone successfully keeping an ant colony inside of a tarantula enclosure without the spider ending up dead or severely stressed because it was unable to get away from the ants climbing on it.
In some cases, where people have attempted to keep tiny scavenger species with their spiders, the ants end up pestering the tarantula so relentlessly that it constantly paces around the enclosure or kicks hairs. Although it may seem like the scavenger ants are harmlessly acting as a cleanup crew when they first move in, eventually, the tarantula will have to molt.
Ants of all types pose a serious threat to a vulnerable tarantula during a molt and can easily fatally injure the spider at this time even if they are only a scavenger species. There is more than one story on Arachnoboards talking about ants killing a molting tarantula.
Why are ants attracted to a tarantula’s enclosure?
Ants tend to seek food and shelter inside of homes during rainy seasons. Once they are in your house, they will enter an enclosure if there are leftover dead prey items. Although they usually aren’t entering the enclosure to directly go after the spider, the ants will take advantage of an opportunity if one presents itself.
Will ants kill a tarantula if they get in the enclosure?
Some ant species are predacious while others are scavengers. However, most ants are opportunistic and will readily take advantage of a vulnerable tarantula that is molting.
I will never forget the time that I found out ants can indeed kill a tarantula if they’re able to get in the enclosure. When I was in first grade, my teacher let me bring an adult female Aphonopelma chalcodes in as the class pet for the week.
Unfortunately, at some point during the day, someone dropped a cookie in the tank. When I came into the classroom the next morning, not only was the cookie swarmed with ants but so was my tarantula who was sitting in a complete death curl.
I remember being so upset my mom had to come to the school to pick me up and excuse me from class for the rest of the day.

How do you get rid of ants without killing your tarantula?
Do not spray Raid or any other aerosolized insecticides inside the room that you keep your tarantulas in. If the ants are actually getting into the enclosures, then it’s important to also keep in mind that they can track poisons in with them that they pick up from bait stations.
Prevent this from happening by using diatomaceous earth or vaseline barriers to stop them from climbing up to where the enclosures are.
I personally use Terro liquid ant baits, which is a Borax-based ant killer. However, after a cursory glance at the reviews, it is worth noting that Terro doesn’t seem to work effectively against all types of ants. So far it has worked for all of the species that I’ve had get into my house here in Arizona. It usually takes 2-3 days for the Terro baits to work.
Some people use Amdro Ant Block around the perimeter of their house (not inside their tarantula room), which is advertised as being effective against fire ants, carpenter ants, as well as 23 other ant species. From what I’ve read on Formiculture, this seems to be more effective than many of the small bait stations. Formiculture is a forum for ant keeping hobbyists, and they also have to deal with foreign ants getting into their colonies.
If you’re dealing with ants that have gotten into the enclosures, as opposed to just finding a trail of them on the floor outside of the spiders, then you will need to immediately remove the tarantulas from the affected tanks.
Everything in the infested enclosure will need to be removed and either disposed of or thoroughly cleaned. Put the spiders into temporary containers so that you can empty all of the substrate out of the enclosure.
Make sure you wash the entire container and all of the tank decorations, like water dishes and hides, thoroughly. Doing so will minimize the chemical trails that the ants leave so that more ants don’t get attracted to the enclosure.
Once you’ve thoroughly cleaned everything you can replace the substrate and add the tarantula back. If you’re having a difficult time getting rid of the ants in your main tarantula keeping room, then it would be advisable to keep the spiders somewhere else until you get the problem under control.
Why do ants keep getting into my tarantula enclosures to eat the dead crickets?
If ants are successfully getting into your enclosures because they are attracted by leftover bits of feeder insects, then you need to first address the immediate problem of the ants.
Once the ants have been eradicated, you can take a look at what brought them there in the first place, which in this case is inadequate spot cleaning if there are dead prey items in the tank. The best way to stop ants from getting into an enclosure is to not give them a reason to do so in the first place.
It’s possible that you will need to revise your maintenance schedule and become more diligent about removing the food bolus the tarantula leaves after eating or any prey items that have died in the enclosure. Both of these items should be regularly removed via spot cleaning.
How do I stop ants from climbing into tarantula containers while I deal with getting rid of them?
Ants will only find the tarantula if there is a direct path to it, so make sure that the shelving you keep your spiders on isn’t touching a wall.
If you use lighting on your spider displays, make sure the cords are positioned so that they run down the legs of the cabinet so that you only have to treat the area around the legs and the outlet.
One way to stop some species of ants from being able to climb into the enclosures easily is to make a barrier using petroleum jelly. This can be done on the outside of the enclosure at the base, or on the legs of the cabinet or table that the enclosures are sitting on. If ants are using cords to access the tanks, then you may need to create a barrier around the wall outlet.
Another option that can stop ants from climbing into enclosures is to sprinkle diatomaceous earth around the location where the ants are entering the shelving unit, as well as around any cracks in floor where they may be coming up from.
Diatomaceous earth is a form of silica that is made up of the fossilized remains of diatoms. It doesn’t directly poison the ants. Instead, the pieces of silica have very sharp edges that easily abrade the cuticle of the ant’s exoskeleton, which causes them to desiccate. You want them to walk through it, which is why you need to locate where the ants are entering.
This should only be used outside of the enclosures, do not put diatomaceous earth inside of your tarantula containers because it will also abrade the spider’s exoskeleton.
You must use care not to accidentally introduce it into the enclosures from your clothing. It’s important to note that you should always work cautiously around diatomaceous earth because the small particles are irritating to the respiratory system, and some people report being allergic to it.
Dry borax can be used as a replacement for diatomaceous earth because it also abrades the exoskeleton which causes dehydration (again, don’t allow it to get into your enclosures or breathe it in).
Some people wipe white vinegar diluted with water on the areas where the ants are climbing, or they sprinkle cayenne pepper down where they don’t want the ants to go. Neither will kill the ants, but they are said to be deterrents for some species.
Peppermint oil infused cotton balls can be used as a repellent by being stuffed into cracks and holes where the ants are coming in from.
Some people recommend placing the tarantula enclosures on top of a pan of soapy water. However, this only effective against some species of ants. There are some types of ants that can easily cross a water barrier.
Final Thoughts on Ants Killing Tarantulas
Ants can and will kill a tarantula if there is a sufficient number of them and the right opportunity presents itself. Preventative measures, such as promptly removing dead feeders and making sure that no direct paths exist going to your enclosures, is the best thing that you can do to stop a problem from developing. If you find a line of ants in the house, remember to never spray pesticides into the air because this can also kill your pet inverts.
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