How Do Hermit Crabs Breathe?

hermit crabs life

Hermit crabs most definitely breathe and they do this through very tiny gills that rely on humid to sub-tropical conditions.

These very small gills are located in the hermit crabs brachial chamber and this chamber together with the hermit crabs gills function like a lung, allowing the hermit crab to breathe the air as humans can.

It may be hard to believe that Hermit crabs can breathe air, but yes they do! Hermit crabs breathe with their gills, and a humid environment to keep them moist. When it’s too dry your Hermit Crab may find it hard to breathe or even die. Always try to keep their tank at roughly 50-70% humidity.

When we discussed sub-tropical conditions above, this is extremely important to know as your hermit crab requires a high level of humidity and warmth and without the proper level of humidity, the hermit crab will suffocate and die.

Are Hermit Crabs Breathing Under Sand?

One fascinating fact you may be very interested to know that not many people know is that when the hermit crab buries himself deep down under the sand that is in his enclosure many fear their hermit crab can not breathe.

This is not true! Your very intelligent hermit crab will tunnel down beneath the sand for darkness, molting, sleeping, and for privacy and as he does so he continuously maintains a few millimeters of separation between him and the sand.

This is how your hermit crab does not suffocate under the sand. Hermit crabs can be under the sand for a long time. This is why hermit crabs need sand in their enclosure.

How Long Can A Hermit Crab Hold It’s Breath?

As with many of the crab family, they all breathe through their gills, Many people do not know these simple facts, as long as they can keep their gills moist they can breathe for 1 to 2 days out of the water.

If you want to talk about a hermit crab holding its breath underwater it is said that a hermit crab holds its breath from 20 minutes to 1 hour. Most common hermit crabs tend to hold their breath for just 5 minutes at a time in the water.

It’s noted that hermit crabs breathe a lot as fish do by dissolving the extracted oxygen element from the waters they live in. Flowing through its gills is what’s known as “hemolymph” to a crab it’s referred to as Deoxygenated “blood”.

Can Hermit Crabs Breathe Out Of The Saltwater?

If you did not know how your crabs breathe most common hermit crabs spend their time in the water and on the sand, So the question is can hermit crabs breathe out of saltwater, The answer is yes, but your typical land hermit crab does not need to be underwater all the time.

Most hermit crabs can be out of saltwater for a long period of time, although they need their gills damp when there not in saltwater. It is also best to keep their habitat humid at all times.

How Do Hermit Crabs Get Oxygen To Breathe

Well, what we know is crabs use modified gills that fill with oxygen, this is located in its brachial chamber this chamber which acts almost like a lung, this is used with its gills they then can breathe through the air and not water.

A way you can think about how they get oxygen to breathe is where the crab’s thorax is located think about the area above your crab’s legs and this is where your crab’s brachial chamber and lungs are located.

Humidity Is Critical For How They Breathe

If you’re just starting out in the crab world it’s best to buy a hygrometer so you can watch the humidity in their enclosure. You could also look at buying a humidity gauge as this can also be used to help them breathe better.

Did you know? Your average household has a humidity level close to 40 or 50 percent having said this your crab needs a level higher than this to breathe.

When you have a too dry of a location you will just end up doing damage to your crab’s grills this can cause them to have problems breathing and they will end up just suffocating, Please also note doe not have humidity over 85 percent as this is too damp and will just cause it to get moldy.

What Can You Do To Help Your Crabs Breathe Better?

We all want our pets to live happy life and keeping them safe is the key to having them around longer. Below are some tips for better breathing and a longer life for your crabs.

  • Use a hygrometer or a humidity gauge.
  • Check the levels daily.
  • Keep the tank area clean.
  • Change out the sand or area once a month.
  • If you use beach sand please bake it to kill germs.
  • Give them an area to climb and play.
  • Clean water is a must! change it daily.
  • Use a de-chlorinated for their water.
  • Saltwater, Hermit crab Salt can be used also.
  • Reptile lamps can also be used.
  • Hermit crab heater.
  • Water helps keep the humidity level at a safe level.
  • Hermit crab Salt.
  • Make sure they are not overcrowded this can lead to stress.
  • They don’t like to live alone.

Ending notes on keeping your crab encloser safe, the humidity should be kept around the 70% mark this will help keep your crab breathing easier and live longer.


Hello, my name is Mackenzie and I have created this website out of my love for all the world's beautiful creatures - great and small. I hope you find this website useful as I take you through various topics about a variety of some of our most loved animals and ways in which you can gain some knowledge on how to care for them properly.

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