Taking care of hermit crabs is something that is usually a lot of fun. For the most part, hermit crabs are low-maintenance pets that don’t require too much attention.
You do need to put some effort in to keep the pets in good health, though. If your hermit crab recently died, you might be wondering what went wrong.
There are actually quite a few things that can cause hermit crabs to pass away. Knowing what causes hermit crabs to die might help you to figure out what went wrong in your situation.
Keep reading to learn about hermit crabs and what causes them to die. This should allow you to understand what mistakes you need to avoid when caring for these pets.
1 – Lack of Humidity
A lack of humidity can easily cause a hermit crab to die. You see, hermit crabs need to live in very humid environments.
To keep hermit crabs safe, the humidity level should stay around 80%. This is obviously quite high, and it’s a lot higher than the acceptable humidity level for a normal home.
So you need to take steps to maintain high humidity in the hermit crab’s tank. Doing this is easier if you use a humidifier.
You can easily purchase a humidifier that will be perfect for the hermit crab’s tank. Often, people use the same type of humidifiers that are used for reptile habitats.
It’s also necessary to monitor the humidity in the tank to ensure that all is well. This means you’ll need a hygrometer so you can keep things at the right level.
Without a humidifier, it’d be hard to keep the tank humid enough for the hermit crab. Since hermit crabs have modified gills that need to be kept moist, it’s important for the environment to be humid enough.
When a hermit crab is forced to live in an environment that is too dry it’ll wind up drying out. The gills won’t stay moist and the hermit crab will die because it can’t breathe properly.
2 – Excessive Heat
Excessive heat can kill hermit crabs for similar reasons to a lack of humidity. Hermit crabs are at risk of drying out when they’re made to live in very hot tanks.
However, you can make hermit crabs too hot. When hermit crabs are put in an environment that is very hot it’ll cause them to dry out.
These creatures have modified gills that must stay moist. When the gills can’t remain moist, hermit crabs aren’t able to breathe oxygen properly.
The temperature in a hermit crab’s tank should remain between 72 degrees Fahrenheit and 80 degrees Fahrenheit. Hotter temperatures have the potential to kill the crab.
3 – Cool Weather (Not Using a Proper Heater)
Conversely, cool weather can be responsible for killing hermit crabs. This is why you’re supposed to use some type of heater for the hermit crab’s tank.
You know that hermit crabs are supposed to live in tanks that stay between 72 degrees Fahrenheit and 80 degrees Fahrenheit. In the winter, it might get cooler than this in the habitat if you’re not using a heater.
Hermit crabs that are exposed to temperatures that are cooler than 50 degrees Fahrenheit might die. They can’t tolerate such cool temperatures.
Temperatures lower than 72 degrees Fahrenheit will stress the crab and make it sick. So using a heater is always for the best.
You can use a standard heater for the tank or you can utilize a heat lamp. It’s important to have some method to keep the tank warm enough to help the hermit crabs survive.
4 – Drowning
It’s more common for hermit crabs to die via drowning than you might think. Hermit crabs have gills, but they can’t breathe underwater.
Marine hermit crabs have normal gills and they live their lives underwater. They cannot survive on land.
Land hermit crabs are the opposite. They have modified gills that can breathe oxygen, and they live entirely on land.
Hermit crabs can drown to death when they submerge themselves in water. This is why you must be careful when putting water dishes in the tank.
The crabs need to have shallow water dishes. You must pick shallow dishes that are just deep enough for the hermit crabs to submerge themselves in the water.
It also needs to be easy for the crabs to get in and out of the water. If a crab gets stuck in the water dish, it could easily wind up drowning.
5 – Stress
Stress has been known to kill hermit crabs. There are many reasons why these crabs might become stressed.
A hermit crab might be stressed if it’s forced to live in an improper environment. For example, putting a hermit crab in a tank that doesn’t have a sufficient amount of sand will cause it to become rather stressed.
Likewise, hermit crabs that are forced to live alone will become lonely and stressed. You need to put your hermit crab in a position to be happy so that it can thrive under your care.
There are many other things that can make hermit crabs feel stressed. Exposure to noise will bother these pets, and that means you shouldn’t put them in noisy rooms.
Excessive light will bother hermit crabs since they’re nocturnal. So will being bothered by other pets such as cats and dogs.
Hermit crabs will get stressed if you try to handle them too often, too. Handling is not a pleasant experience for hermit crabs.
Stress issues that aren’t addressed might eventually cause the hermit crab to die. You might notice the hermit crab will start losing legs here and there when it’s very stressed.
6 – Fighting With Other Crabs
Sometimes hermit crabs will fight each other. This usually only happens when hermit crabs are fighting over shells.
Hermit crabs are social creatures that like to live in groups. If you don’t have enough shells in the tank, your hermit crabs could come into conflict with one another.
This is why it’s imperative to keep multiple shells of each size in the tank. It helps hermit crabs to avoid feeling the need to fight with each other.
Hermit crabs won’t always kill each other when they fight. Sometimes one crab might simply get injured.
Regardless, it’s important to try to keep fighting to a minimum in the tank. Do what you can to keep problems like this in check.
7 – Exposure to Chemicals
Hermit crabs are very sensitive to chemicals. Exposing hermit crabs to chemicals is a bad idea when you want to keep them healthy.
Did you give your hermit crab tap water? Tap water contains traces of chlorine, and that can easily cause hermit crabs to die.
When hermit crabs are exposed to chlorine it causes problems with their gills. They wind up suffocating due to chlorine exposure.
Other chemicals can also kill hermit crabs. So you’re not supposed to use chemicals to clean the hermit crab’s tank.
You should even be careful not to put the hermit crab tank too close to certain types of painted surfaces. Chemicals are truly not good for these creatures.
8 – Being Disturbed During Molting
Another common thing that kills hermit crabs is being disturbed during molting. Molting is something that most hermit crabs do every twelve to eighteen months.
When a hermit crab is molting it’ll bury itself in the substrate and it’ll be very still. Some new hermit crab owners get worried about their pets during this time.
They might choose to check on the crab to see if it’s okay. Doing this is detrimental to the crab.
Hermit crabs that get disturbed when molting become rather shocked. It’s possible that the hermit crab will die due to being bothered while molting.
If the hermit crab doesn’t die, it might suffer health consequences. For example, the crab might lose a leg or two.
Never bother molting hermit crabs. Be patient because molting can take as long as several weeks or even months in some cases.
Do Hermit Crabs Come Out of Their Shell to Die?
No, it’s not common for hermit crabs to come out of their shells to die. Hermit crabs will generally stay inside of their shells when they’re dying.
When you see a hermit crab outside of its shell, it’s more likely that it’s looking for a new home. It could be testing out new shells because it has grown recently.
Excessive heat can cause hermit crabs to come out of their shells, too. If the heater or heat lamp is too hot, you might need to make some adjustments to protect your pet.
Just know that seeing a hermit crab come out of its shell isn’t necessarily an indication that it’s about to die. It is indeed unusual for hermit crabs to stay outside of their shells for long, though.
Typically, hermit crabs only leave their shells if they’re switching shells. Sometimes there might be other reasons for hermit crabs to briefly leave their shells, but they won’t stay outside of a shell for long.
How to Tell if My Hermit Crab Is Dying
Does your hermit crab appear to be in poor health? The hermit crab might look sickly if it’s dying.
Sometimes you might see that hermit crabs will act strangely when they’re on the verge of death. They might not be as interested in food as usual.
Hermit crabs might start losing their legs if they’re very stressed or sick. You can take all of these situations as signs that the hermit crab could be on the verge of death.
However, it’s important to note that these could be signs that the hermit crab is simply sick. Depending on the situation, you might be able to turn things around and keep the crab alive.
When a hermit crab has actually died, you’ll notice that it will be completely motionless. Also, you’ll smell a foul smell that is similar to the smell of dead fish.
How to Get Dead Hermit Crab Out of Shell
Do you want to remove the dead hermit crab from the shell? Doing this might be kind of difficult at first, but there’s something you can do to make it a lot simpler.
Grab the dead hermit crab and place it in a plastic bag. Preferably, you want to use a plastic baggie that is capable of sealing.
Place this sealed plastic bag in the freezer for a few hours. After three or four hours have passed, you can remove the bag from the freezer.
The dead crab’s body should be stiff after being placed in the freezer for so long. This makes it a lot easier to grab onto the crab and pull it out of the shell.
You can use an implement such as tweezers or small tongs to try to remove the crab if you don’t wish to touch it with your hands. Either way, you’ll want to wash your hands thoroughly after you’re done.
Once the dead crab is out of the shell, you should get rid of the body safely. Boil the shell if you want to reuse it.
What to Do With a Dead Hermit Crab
When a hermit crab dies you’re going to want to remove it from the habitat. There could be something wrong that caused the crab to die, and you don’t want the other hermit crabs to get sick.
So removing the crab as soon as possible is the best course of action. Take all of the living hermit crabs and move them to a temporary habitat while you clean things up.
Grab the dead hermit crab and put it in a plastic bag for now. Keep the bag sealed and set it aside somewhere safe.
Clean the tank thoroughly. This is going to take a little bit of time to clean the habitat as thoroughly as you need to.
You should go ahead and remove the substrate completely. Throw away all of the sand and gather any gravel that you’re using.
Gravel, decorations, and rocks can be boiled to make them safe to reuse. Wipe the tank down and clean it well so that it’ll be safe for the crabs.
Replace the substrate by adding as much new sand as you need to. Put the gravel, decorations, and rocks back in the tank after they’ve been boiled, dried, and cooled.
Now you can put your living hermit crabs back in the habitat. Take your dead hermit crab and dispose of it.
Disposing of the hermit crab can be done in several different ways. Since it’s a pet, you might want to give it a proper burial.
You can bury your dead hermit crab deep in the yard if you want to. Many people choose to bury dead pet hermit crabs while they’re still in their shells.
If you want to reuse the shell, it’ll need to be boiled before it can be placed back in the tank. Be sure to do things right to avoid spreading diseases to the healthy hermit crabs in the tank.
Jeff has always enjoyed having pets, but as a child, he was drawn to his family’s fish tank. Being able to maintain a small ecosystem and observe the behaviors and interactions in the underwater world peaked his interest early on and has kept him hooked until this day. On Avid Aquarist, Jeff shares everything he’s learned about helping aquatic life survive and thrive in a home aquarium.