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Why Is My Hermit Crab Upside Down? (6 Possible Reasons)

Why Is My Hermit Crab Upside Down? (6 Possible Reasons)
The purpose of this blog is to share general information and is written to the author's best knowledge. It is not intended to be used in place of veterinary advice. For health concerns, please seek proper veterinary care. In addition, as an Amazon Associate I earn from qualifying purchases.

We all need to take excellent care of our pets and keep them safe and healthy. Depending on your pets’ species, you might have to face a few strange situations. It’s what happened to a friend of mine not too long ago when he got a hermit crab as a pet. Everything was fine until one day when he found his hermit crab lying upside down.

There are many reasons why a hermit crab might be upside down. Hermit crabs can get their shell stuck between two objects. Some hermit crabs get used to being upside down as pet shops tend to put them upside down to attract attention from clients, or when they are sick or molting, to name a few.

Hermit crabs are becoming more popular as pets, and it’s essential to know how to take care of your crab correctly. I wanted to help my friend, so I did research and found fascinating information. I will share what I found on why you might see your hermit crab upside down.

Why Is My Hermit Crab Upside Down?

Hermit crabs are curious by nature and love to explore their environment. Hermit crabs spend more time upside down than most people realize. When most hermit crabs are in pet stores before they are bought, people usually turn them upside down to attract more attention, so they sell easier.

They can get used to being upside down a lot. Your hermit crab being upside down may be a comfortable position for it, but it can be an indication of something else if this isn’t normal behavior for your hermit crab.

It can also be an indication of other issues, including health concerns. Here are some reasons why a hermit crab might be upside down.

1 – Hermit Crab Molting

Gray Hermit Crab in Shell

One of the likeliest reasons for your crab being upside down is that it’s molting. A molting hermit crab will try to burrow into the sand and will lie upside down when molting. They do this to protect themselves as a defense mechanism as they are vulnerable when they molt.

If you have noticed that your hermit crab is upside down and want to know if it might be because it’s molting, then think back on the previous few days; if you have noticed any of these symptoms and signs, then it’s likely that your hermit crab is molting:

Exaggerated Eating Habits

Suppose your hermit crab was eating and drinking much more at least two weeks before it started molting. If you haven’t noticed an increase in food intake, try leaving out more food over the next few days, and if you see they eat that much, then it’s a good indication that they are starting to molt.

Glazed Look in Its Eyes

The stalks of the hermit crab’s eyes will turn dull and then white. Their eyes will start to look dull and glazed over, turning whiter. It’s because the exoskeleton is lifting from the eyes and being replaced by a new bigger exoskeleton.

Constant Digging

If you see your hermit crab constantly digging in the sand, preparing the sand, and digging around the whole day, it might be getting ready to molt.

Grey Colored Exoskeleton

If you see the exoskeleton of your hermit crab becoming dull and turning grey, they are probably going to molt soon.

If you have noticed these symptoms in your hermit crab, it’s probably molting. To be sure, you can check on your hermit crab a few times during the day to see if you observe any of these signs. Remember that hermit crabs are usually hidden and less active during the day, but you might be able to check for tracks around their hiding spot.

If you are sure you have seen at least a few of these signs, then it’s best to carefully dig around the sand your crab has dug itself into, gently pick them and their shell up and place them in a separate tank to molt in privately and safely.

2 – Hermit Crab Trying to Escape

If you have ruled out molting and you see your hermit crab keeps hiding under the sand, flops upside down, or tries to escape the aquarium. Human houses have lots of unfamiliar stimulation, and hermit crabs get anxious quickly.

Hermit crabs tend to explore their tanks, and this means they might climb the tank and cling to the roof of the tank just because it likes to, but if it stays upside down, you need to consider that it might be unhappy.

You need to keep an eye on the following to ensure your hermit crab feels comfortable and safe:

Your Hermit Crab Might Be Bored

When hermit crabs are bored or without company, they tend to try and climb out of their enclosure. It would be better to buy at least two hermit crabs to keep each other company.

Not Enough Space in the Tank

If you have your hermit crab in a too-small aquarium, it can get frustrated and try to escape. Instead, get a bigger tank and fill it with vines and objects for your crab to explore; it will keep it busy and happy.

Wrong or Lacking Environment

If your hermit crab is housed in the wrong environment, it will be unhappy and might become unhealthy; the wrong environment includes low heat and light or dark contrast.

The Hermit Crab Might Be Stressed

Some hermit crabs don’t adjust quickly to captivity and might become anxious, frustrated, and stressed. If there are no other signs of issues, it might try to get out of the tank for this reason.

Hermit Crab Breathing Issues

If there are toxins in the atmosphere, the hermit crab might suffocate; try placing the crab in a different environment to see if the breathing improves. If it does improve, you might need to empty the tank, clean and refill it to get rid of the toxins.

Dietary Issues Could Be a Problem

According to leading experts, a hermit crab needs a varied diet, and if your crab doesn’t get a balanced mix of food, it might try to escape to get the food it needs. Try different foods to see what your hermit crab likes and dislikes and give as much of the food it likes, switching it up each day so it won’t get tired of the same food every day.

3 – Trying To Protect Itself

A Hermit Crab Hiding in Its Shell

When you have more than one hermit crab in a tank, they might try to fight over a shell. Hermit males tend to grow quickly, and they will abandon the smaller shell and look for a bigger one. If the bigger one happens to belong to another crab, the crab needing a shell will start rapping on the bigger shell as a challenge to its occupant to get it to fight for the shell.

When this happens, the hermit crab will flip onto its back to exit the shell faster and easier or to hide deeper in its shell. Even though hermit crabs have a few disputes, they are social animals and crave the company of others.

4 – The Hermit Crab Might Have Fallen

When hermit crabs explore, they like to climb as high as possible. Sometimes they hang upside down on the aquarium roof. Because they are great climbers, it has been noted that they sometimes fall asleep in an upside-down position. It could be the reason they fall. Gravity still plays a role here, and as the crab falls asleep, it relaxes, and gravity pulls it down.

It’s essential to check your hermit crab for injuries if you suspect it might have fallen. Hermit crabs are known to love climbing in the wild and have been seen in trees close to the water. So it’s a great idea to put some branches and vines in its habitat, it will keep it busy and exploring.

5 – Your Hermit Crab Might Be Trapped

Because hermit crabs carry their shells around, they can get stuck between two objects and become stuck on their backs. Hermit crabs are very sensitive and scare easily, so something as innocuous as a light or a new object in their tank might lead them to scurry to a hiding spot.

Hermit carbs can get easily trapped this way as they don’t realize they misjudged the space between two objects until it’s too late and they’re stuck, or get flipped upside down and have a hard time flipping themselves right side up.

You can remove one of the objects it’s stuck between but be careful to wait until it has calmed down as it might pinch you in self-defense if it feels scared or that you are removing its hiding place. Usually, after it’s calm, it will use the other object as leverage to get the right side up.

6 – Unfortunately, It Could Be Dead

Hermit Crab Upside Down

There are times when your hermit crab could be dead and not molting or hiding. If you find your hermit crab is upside down or it’s buried itself in the sand, you might want to check it now and then as it might be dead.

Typically if you don’t see it move within a few days to a week, you need to pick it up and smell it. If it’s dead, there will be a strong fishy, salty decaying smell, and it will be utterly unresponsive to you picking it up or other sudden changes.

The other sign that your hermit crab might be dead is if you find the other crabs gathered around the shell of the upside-down crab; they will gather as a dead crabs body will emit a specific pheromone to let the other crabs know there is an empty shell available.

Is It Dangerous For a Hermit Crab to Be Upside Down?

As discussed, hermit crabs like to be upside down if they aren’t stuck that way. They like to hang from aquarium screens and sometimes sleep upside down. Usually, they are fine this way and can turn themselves over by using their strong legs and objects around them. It’s not easy for crabs to do so as they need something to use as leverage to get right-side up.

It could be dangerous if the reason for your hermit crab being upside down is because it has fallen or is sick. It could also be weak; if it’s going to molt and needs more food, you might not realize it, then it might need food. Leave extra food and see if it helps.

Should I Turn My Hermit Crab Right Side Up?

Hermit crabs are fine turning themselves over and might be on their back by choice. The best way to see if they are there willingly is to observe them carefully. Usually, you will see it struggle to get up if it’s unable to turn itself over. You can help turn your hermit crab over, but if it goes back to lying on its back, leave it.

If you see the crab in distress and in need of help, gently put your hands to the side of the shell in the sand, scoop it up, and put it right side up. Be careful when doing this, as there might be another crab beneath the upside-down one.

Check for signs of molting, and if the signs are there, then separate it from the other crabs and give it a secure and safe tank to molt in privacy. Molting can take up to three months and is very stressful for the crab.

It’s crucial to remember that you should never pull hard or yank your hermit crab out of the sand or its shell to turn it over. You will tear some legs off by doing this; be very gentle because even though their limbs will grow back, they will have limited mobility, which could be very stressful to your hermit crab.

Final Thoughts

Hermit crabs will be upside down if they are molting, stressed, scared, or stuck. It’s best to give them time to recover on their own, but if you see them struggling, you should turn them back over. Hermit crabs are fine being upside down, and some even prefer being that way, but it’s not good for them to be upside down for extensive periods.

If you don’t see you’re hermit crab eating, drinking, or moving for at least a week, then it’s time to give it a sniff and see if it might be dead; hopefully, it’s just molting. It’s crucial to separate it from the occupants in its tank if you see signs of molting.