Can Hermit Crabs Breathe Underwater: What You Need to Know for Their Survival

Yes, hermit crabs can breathe underwater. They usually stay submerged for 10 to 15 minutes and come up for air. Keeping hermit crabs in water tanks is not recommended as they will eventually die from lack of oxygen. They can also avoid water altogether by sticking their head out of the sand and breathing through unique slits in their carapace. Therefore, hermit crabs can survive in water if they are kept fresh and well-oxygenated.

Is It Safe to Keep Hermit Crabs Underwater?

Yes, it is safe to keep hermit crabs underwater for not longer than 30 minutes. However, they should not be kept in water tanks as the oxygen levels will eventually become too low, and the crabs will die. Additionally, they should be given a water dish and appropriate shelter when kept underwater. 

So, in a nutshell, hermit crabs can breathe underwater but should not be kept in water tanks and should be provided with appropriate shelter when kept underwater.

Facts About How Hermit Crabs Breathe

Hermit crabs cannot breathe air or water. They can only breathe through their gills. In addition, they cannot survive for long if they do not come up for air. Provided they have access to fresh water and can escape from high-pressure areas; hermit crabs can live relatively everyday life in an aquatic environment.

Signs That Hermit Crabs Are Suffocating

They are likely suffocating if you see your hermit crab gasping for air or semiconscious air. Immediately remove the crab from the water and place them in fresh water until a veterinarian can be contacted. Plus, if you notice any lesions, redness, or swelling on the crab’s body, it is advisable to seek medical attention.

Can Hermit Crabs Drown?

Yes, hermit crabs can drown. They can drown if they don’t get enough air and water. You can tell if a crab is getting enough air and water by looking for signs of distress, like waving their claws or crawling onto land.

If your crab is kept in a water tank, it is essential to provide appropriate shelter and keep the water level low so the crab cannot escape. Additionally, ensure that the crabs have access to fresh water and food. Finally, ensure the tank is well-lit and high-pressure areas are avoided.

How Do Hermit Crabs Breathe Under Sand?

Hermit crabs can breathe under sand if they have access to air and water. However, this requires exceptional circumstances – for example, a sand tunnel entrance. Additionally, if your crab cannot escape, it may suffocate. So, apart from breathing, hermit crabs need to eat and drink, expel waste products, and have access to fresh water to survive.

Two Types of Hermit Crabs

Land hermit crabs are found mainly in warm climates. These crabs live in tunnels dug under the sand and can survive for months without food or water. Marine hermit crabs are found mainly around the world’s oceans and live on coral reefs.

They need to hunt for food on land and make their homes in crannies of rocks. Additionally, land hermit crabs can easily escape from their homes if there is a problem, like high water levels. Marine hermit crabs are less likely to do this because they live in protected areas on coral reefs.


Underneath sand, land hermit crabs can breathe and live. These animals are often found in warm climates and make their homes by digging tunnels underground. The entrances to these tunnels may be disguised or have a sand cover that helps to keep them hidden from predators.

Although these animals can survive for some time without food or water, they typically hunt and scavenge for food. Land hermit crabs can dash on all fours to escape danger and climb trees.


Marine hermit crabs are found in many different parts of the world. They build their homes out of coral and live among the shells of starfish, sea anemones, and other marine creatures.

Unlike land hermit crabs, these animals must find food to survive. Marine hermit crabs usually eat small crustaceans or fish they catch with claws or bills. If there is a problem like high water levels, some marine hermit crab species can escape from their homes by swimming through salt water to a new area.

Humidity Is Critical for How Hermit Crabs Breathe

One of the main problems hermit crabs face is humidity. When they’re on land, their gills don’t work well when it’s humid because the moisture blocks their breathing passages. On the other hand, Hermit crab species that live in warm climates may have to find a way to deal with high humidity levels, such as by digging tunnels underground or living in groups.

Ensure to provide enough moisture to keep them happy and healthy by keeping the humidity level in your home constant. For example, hermit crabs can’t live in dry climates, so be sure to provide them with the moisture they need to survive.

What Can You Do to Help Your Crabs Breathe Better

One way to help your hermit crabs breathe better is to keep the humidity level in your home constant. This will allow them to open their gills and breathe air. Another helpful thing you can do is provide them with an area where they can dig tunnels underground or live in groups.

This will protect them from the high humidity levels found near bodies of water. You can also add fresh flowers and seaweed to the tank for added oxygen.

Additionally, place a thermometer in the water to monitor the temperature and humidity. If your hermit crabs show any signs of distress, like difficulty breathing or sluggishness, take them to a vet as soon as possible.

Knowing if a Hermit Crab Can Breathe Underwater

Observing your hermit crab gills is one way to know if it can breathe underwater. When they’re on land, their gills don’t work well when it’s humid because the moisture blocks their breathing passages.

However, some hermit crab species that live in warm climates may have to find a way to deal with high humidity levels, such as by digging tunnels underground or living in groups.

If you’re unsure if your hermit crab can breathe underwater, place them into the water and observe how they react. If they become distressed or start showing signs of difficulty breathing ( like sluggishness or breathing problems), take them to a vet.