
My A. insubtilis tarantula after succumbing to DKS. It’s been flipped on its back, but this is the standard tarantula “death curl”.
The “death curl” … What is it?
Perhaps no phrase causes more fear and confusion for those new to the hobby than that of the dreaded “death curl”. I follow several tarantula message boards and at least once a week, a panicked keeper will come on asking how to save his/her dying pets. In some cases, it’s the real deal, and the animal passes away or is saved by quick intervention. In others, photos of the T reveal that the specimen was never in a “death curl” at all, and that the keeper misidentified an innocuous position as something more deadly.
When most tarantulas die, they don’t flop onto their backs as many believe (this is actually a MOLT!), or just stop what they are doing and die in a normal legs spread position. In the majority of instances, their legs curl beneath them in a very unmistakable position, one that hobbyists refer to as a “death curl”.
To see what this looks like, make a spider with your hand by arching your fingers and putting your fingertips on a hard surface like feet. Now, loosely curl in your fingers until your thumb and fingertips are touching and your hand is resting on your third knuckles. Congrats! Your hand is now doing a “death curl”.

My H. villosella sling in an ICU after I found it in a death curl. Unfortunately, it did not make it.
Now, tarantulas are known to rest in all sorts of strange and sometime awkward positions, and unfortunately, a few of these normal postures can resemble a curl. Finding a T in this position can throw those new to the hobby into hysterics as they worry that their prized pet is checking out. For example, a stressed tarantula will often pull all of its legs up close to its body so that its knees cover its face and carapace. This position in particular freaks out many a keeper and, unfortunately, usually leads the concerned owner to takes steps (like moving the animal, spraying it, or poking it) that will only lead to more stress.

This tarantula above is NOT in a “death curl”, but is bringing its knees up over its head because it’s stressed after a rehousing. A special thanks to Caroline Dellinger for letting me use her photo!

My mature male H, incei gold after dying of old age. Notice how the legs are curled completely beneath his body.

A side view of a death curl (an H. incei gold mature male). Notice again how the legs curl beneath the specimen’s body.
The death curl can occur when the tarantula is either too weak from sickness or old age, has sustained an injury leading to the loss of hemolymph (the tarantula’s “blood”), or is dehydrated. If these instances are severe enough, the spider will have difficulty maintaining the pressure required to keep its legs outstretched, and its limbs will start curling in underneath it.
For a tarantula entering a death curl-like position, all hope may not be lost. Although for some specimens, the curl might signify an irreversible, natural death, for others it could serve as a last chance warning sign that action is needed. If you suspect that your tarantula is in the “death curl”, here are a few a few question you should immediately ask yourself:
- Is the species old or a mature male? Although many species are long-lived, they all eventually die. Also, mature males of many species generally don’t live for too long after their ultimate molts, and some folks are surprised when a seemingly vibrant and energetic adult T suddenly curls up and dies. Many folks also buy supposed adult “female” tarantulas from local pet stores only to discover later that they are matured males on the last legs of their lives. Always take age and sex into consideration first.
- Has the T been injured? Accidental loss of a limb or a fall from a large height can lead to injury, bleeding, and death. So can a particularly bad molt. Examine the species to see if there is any milky white fluid (hemolymph) leaking from its joints or its abdomen. If so, you can try clotting the wound using corn starch, then put the animal in an ICU (a smaller container with moist paper towels, access to drinking water, and a little extra warmth if possible).
- Is the animal possibly dehydrated? This is common one, and one that can be prevented or fixed if caught soon enough. A dehydrated spider will begin to go into a death curl as it lacks the fluids to maintain proper pressure. Slings are particularly susceptible to dehydration as they are not able to hold their fluids as well as their juvenile and adult counterparts. Those who use heat lamps or other direct heat measures on their T enclosures also run the risk of baking the animal, thus dehydrating it. If you suspect your T is dehydrated, get it into an ICU immediately. Most will bounce back after they get some fluids. And if the animal was dehydrated, then its time to reexamine your husbandry.
There are obviously other ailments that can lead to a tarantula death curling (mites and nematodes are sometimes mentioned), but the three options listed above are the most likely.
And, as a friendly reminder…
IF IT IS ON ITS BACK, IT IS NOT DEAD OR IN A DEATH CURL!
That’s right, this is normal behavior; this is the position they get in to molt.
DO NOT touch a spider in this position.
DO NOT flip over a spider in this position.
DO NOT throw away, flush, or bury a spider in this position.
DO NOT blow on it.
DO NOT spray it with water.
DO leave it alone and let it complete the exhausting task of molting in peace. Molting is a natural occurrence for a tarantula, but it is also a period where they are quite vulnerable. Any fiddling with the animal could prove deadly to the T.
If you have a further question about whether or not your tarantula may be in a death curl, try a Google Image search for “tarantula death curl” and compare. Or, visit Tarantula Forum or Arachnoboards to seek the advise and opinions of other keepers.