do hermit crabs leave their shell to die?

Do Hermit Crabs Crawl Out of Their Shell To Die?

Hermit crabs spend their lives within a shell. Aside from leaving temporarily to molt or upgrade to a bigger shell, hermits will never exit their homes. That can leave you puzzled when your hermit crab abandons its shell, wanders to a different part of the tank, and dies. Many animals are known to choose a specific area to die, so it’s logical to assume hermits are the same. You may even think the hermit was leaving the shell open for the living members of its colony.

Hermit crabs don’t specifically crawl out of their shells to die. Most will die within their shells, as this is the safest, most comfortable place to be. If it seems like your hermit crawled out specifically to perish, it’s just a coincidence. The hermit crab may have died from dehydration while outside its shell, failed a molt, or got into a fight.

If your hermit is outside of its shell, it’s not looking for a burial ground. Instead, it’s usually an accident or a temporary exit. It might also be at risk of dying simply because it’s out of its shell. Whether they’re contending with illness, injury, or stress, hermits will try to stay in their shells until the very end. That often leaves owners with the responsibility of extracting the body when their hermit crab dies.

Do Hermit Crabs Leave Their Shell to Die?

Hermit crabs do not vacate their shell specifically because they know death is near. In fact, many prefer to stay within their shells if they’re ill or injured. That’s because it’s:

  • The most comforting space for them
  • It keeps them hydrated and protected from the elements
  • It protects them from predators or other hermit crabs

As a hermit crab tries to heal from an injury or weather an illness, the shell is the best place to be. However, if it can’t overcome the effects on its body, it can die inside its home. This leaves most owners with a need to clean out the shell once their hermit crab passes away. In the wild, it would decompose inside, or other hermits would drag out the body to claim the shell.

As such, if you see your hermit crab leave its shell, it does not necessarily mean its time has come. If it dies later, it could be unrelated, or it might’ve died from the absence of its shell alone.

Hermit Crab Left Shell And Died

Many animals appear to sense when they’re about to die and enact certain behaviors as a response. If your hermit crab perished after leaving its shell, it’s logical to assume it did the same. It left the shell so it could die in peace, maybe even preserving the shell for another hermit.

As far as the limited studies can tell, this is not the case. Hermit crabs show no obvious behaviors when approaching death, aside from symptoms of disease or illness. They will not act in a special way or try to prepare themselves for the end. With that in mind, if your hermit crab left its shell and then died, it’s likely because:

It Was Already Sick Or Injured

Hermit crabs that are extremely sick or have lost a limb may be unable to keep themselves inside of their shells. This can lead to them falling out when they move around if they can move at all.

Once the hermit has fallen out, it may be unable to get back into the shell. It will seem like it purposefully vacated the shell and refused to go back. In truth, it wanted to but couldn’t. It may have succumbed to an outside threat, if not the original injury or illness, shortly after. The fact that it left its shell was an accidental byproduct, not a sign.

how to get a dead hermit crab out of its shell

It Was Harmed While Changing Shells

Once a hermit crab outgrows its old shell, it will try to find a larger replacement as soon as possible. This will require it to leave the shell and quickly slide into a new one.

Hermit crabs are prone to stealing shells and fighting over them, however. Different species will also prefer different types of shells to reside in, according to Pacific Science. If you don’t have enough options, the hermits may feel their choices are limited and fight.

If your hermit was making a switch and got confronted by another hermit, things might’ve turned nasty. You’ll then find your hermit dead and outside of its shell. If you didn’t witness the fight, a cursory glance at this evidence could make you think it left the shell and died on purpose.

It Became Dehydrated

If your hermit crab lost its shell to another hermit, or it left for another reason and couldn’t get back in, it might’ve died simply because it lacked a shell. According to the Journal of Experimental Marine Biology and Ecology, hermit crabs need a 50 percent increase in oxygen consumption instead of hermit crabs without shells on their back. They also rely on humidity to properly absorb oxygen from the air.

Hermits maintain the right balance by keeping the inside of their shell moist. If the hermit was out of its shell, for whatever reason, and couldn’t get back in, then it might’ve died. Since it’s hard to verify this as an accident with a glance, it’ll seem like a hermit purposefully leaving to die.  

It Needed A Better Shell Because Of Danger

Hermit crabs use their shells for protection, so they will hide inside if they feel threatened. In some cases, a hermit crab may feel its shell isn’t up to the challenge. As such, it will pick the best moment it can to switch shells.

Another article from the Journal of Experimental Marine Biology and Ecology found that hermit crabs in sub-optimal shells will tend to abandon their homes, especially in times of danger. This danger could be a direct threat to its life, such as illness or being trapped under debris. It may also feel so stressed that it thinks it’s in danger.

No matter the reason, hermit crabs cannot be without a shell for too long. This leaves them overly exposed to their surroundings, dries them out, and makes them lethargic. If your hermit can’t successfully switch to a better option, it will die without a proper shell to protect it.

Highly Stressed

The hermit crab may have vacated its shell and failed to discover a new one because of stress. Despite their seemingly hardy nature, hermit crabs tend to stress out very easily. Something as simple as a change in humidity or temperature may cause the hermit to leave its shell. Once outside, the stress could’ve made it sick or inhibited its ability to find the new shell. 

Shell Was Unsafe

A sick hermit crab will vacate its shell if it feels it has been contaminated. Your hermit might have mites, particles of sand, or other objects lodged between its soft abdomen and the shell. It may also have gotten fungal or bacterial infections that led to skin disease.

Once it leaves the shell, it may die due to its illness or being without a shell. That can make it appear like the hermit left specifically because it knew it was about to die, but it’s just coincidental.

Failed A Molt

Molting is a dangerous process for hermit crabs. Some will leave their shells temporarily and bury themselves in the sand to begin the process. Here, they will begin shedding their old skin and creating a new, larger one. Throughout this ordeal, the hermit may be vulnerable to:

  • Attacks from other hermits
  • Cave-ins from the sand
  • Environmental changes

If the hermit leaves its shell, runs away to bury itself, and then turns up dead, that’s usually the cause. It wasn’t trying to hold a burial because the end was near. It didn’t even intend to die when it left.

Do Hermit Crabs Die Inside Their Shell?

Most hermit crabs will die within their shell. There is no reason to brave the scary, outside world if the hermit knows it’s sick or injured. Hermit crabs also live anywhere between 5 to 15 years. Older hermit crabs will be just as eager as young ones to stay within the comfort of their shells.

Whatever the cause of death is, your hermit crab will likely try to overcome it within the safety of its mobile home. If it fails, the body will remain inside until:

  • It decomposes
  • Another hermit crab pulls it out
  • You remove the body

A dead hermit crab will take on an unpleasant, fishy odor. You will definitely be able to smell if you get anywhere near its enclosure. That is often the first signal you have that a hermit crab has passed away.

How to Get a Dead Hermit Crab Out of its Shell

If your hermit crab dies within its shell, you can dispose of the body shell and all or fish the pet out. The latter option is often preferred, as the living members of your hermit colony will still get some use from its shell.

There are 2 main approaches to getting the deceased hermit out of its shell. You can use:

Insects

Find an anthill or other patch of soil rich in insect life. Bury your crab in this anthill or patch of dirt so that the insects will clean out the old carcass for you. This method is thorough and leaves little odor behind.

Cold Temperatures

Freeze and thaw the shell at least 2 times for several hours each. The hermit crab’s body will become stiff and easy to remove with a toothpick, tweezers, or another tool.

Remember to clean the shell afterward to kill any lingering bacteria. Typically, soaking shells in a 1-part water and 1-part bleach or alcohol solution will do the trick. Sterilizing the old shell in a pot of boiling water for around 15 to 20 minutes is also a good method of cleaning it.

Hermit crabs will stay in their shells to die. If you find your hermit out and roaming free, it hasn’t decided the time for its end is now. Instead, it could be molting, need your help to find a shell, or may be unable to return on its own.