Do Hermit Crabs Lay Eggs? The Fascinating & Strange Process


by Simon Griffiths



Do hermit crabs lay eggs or do they give birth?


is there anything you can do to make to make a hermit crab have babies/reproduce?


The reproduction of hermit crabs is a little-known phenomenon because they rarely reproduce in captivity. So, very few hermit crabs owners have experienced it.

This post covers every detail about how hermit crabs reproduce by answering these questions:

  • Do hermit crabs lay eggs or do they give birth?
  • How do they lay eggs?
  • What do crab eggs look like?
  • How many eggs do they lay?
  • How do the eggs hatch?
  • How many eggs survive?
  • What happens if the eggs are not fertilized?
  • Do hermies lay eggs in captivity?

With that out of the way, let’s get into it. 

the development of hermit crab eggs in four stages
A photo showing thousands of brick hermit crabs’ eggs, they then turn grey and finally hatch into zoea


Do Hermit Crabs Lay Eggs?

Yes, female hermit crabs lay thousands of brick-red eggs that attach to their pleopods for up to one month until they mature. The eggs are hidden in the shell since their abdomens are always tucked in the shells. A female hermit crab lays up to 50,000 eggs depending on its size. 

What Do Hermit Crab Eggs Look like?

Hermit crab eggs are tiny and circular in shape. The eggs are attached to each other forming a cluster or lump. They are initially brick red but turn grey as they mature. 

 Because hermit crabs rarely change their shells when pregnant and hermit crabs don’t normally lay eggs when in captivity, spotting the eggs is not common. In case your hermit crab lays eggs in captivity it means you are doing a great job. Hermit crabs will only lay eggs if they are happy and comfortable and if the conditions are optimum.

 After being on the pleopods for one month, the female hermit crab then lays the eggs in salty water so that they can hatch into larvae hatchlings called Zoea. For the eggs to hatch, they require very specific conditions, or else they will rot and go to waste.

As you can see in the photo below, the eggs are tiny and circular-shaped.

hermit crab eggs

How Do Hermit Crabs Lay Eggs?

Due to the nocturnal nature of hermit crabs, it is almost impossible to see hermit crabs laying eggs or even mating. Keep in mind that these decapod crustaceans have to get out of their shells briefly in order to mate.

Their genitals are located at the far end of the abdomens and they can’t access them with their shells on. So, what happens is that the male and female crabs will get out of their shells and mate.

The mating process is quick. It is just a matter of the male depositing the spermatophore into the female. If the hermit crabs stay long outside their shells, there is a chance that other crabs will steal their shells. Mating takes only take a minute or less, making it safe for both crabs.

If fertilization was successful, the female hermit crab will lay eggs, but they will remain attached to her abdomen. She’ll doesn’t deposit her eggs in a hole or something of the sort. She’ll then carry them with her for a month and then deposit them in salty water. 

This is important:

A female hermit crab will only lay eggs if it mates with a male hermit crab. If you only have female hermit crabs, they cannot lay eggs.  So, if you want to try to hatch baby crab eggs, ensure you have a male and a female. Also, all hermit crab eggs are fertilized.

In most cases, you won’t notice that your hermit crab is pregnant and she will just drop her eggs in water or on the substrate without you even noticing.

What Do Hermit Crab Eggs Look Like?

If you own pet hermit crabs, you might be curious -what do hermit crab eggs look like? If a female hermit crab has laid eggs you can see them if you peep through the opening of your crab’s shell. You will see a lump of circular-shaped eggs that is brick red in color or grey if they are almost hatching.

A female hermit crab carries her eggs for about a month and during this time, the eggs will have a brick-red color. The eggs occur in clusters and they’ll be attached to each other the whole time. If you continue monitoring the eggs, you’ll notice a change in color. They should start turning to dark gray as soon as the yolk supply is depleted.

After one month the female crab will begin depositing her eggs in the ocean or saltwater for those in captivity. These eggs will hatch immediately after coming into contact with salt water.

The new larval hatchlings then spend up to three months in the water before they can eventually start living on land. Remember these hatchlings need to find their first shells before they can spend time out of the water.

How Many Eggs Do Hermit Crabs Lay?

Hermit crabs are adapted to laying eggs in large numbers in order to increase their survival rate. It is impossible to count the number of eggs as they are too small and hidden deep in the shell. Carcinologists indicate that hermit crabs lay up to 50,000 eggs depending on the size. A small hermit crab will have a few thousand eggs while a fully-grown female will lay tens of thousands of eggs. See our post on how big do hermit crabs get.

What Should I Do If My Pet Hermit Crab Lay Eggs?

If you are taking good care of your hermit crabs and providing them with what they need, including food and water, then there is a chance your female will lay eggs. Unfortunately, there is very little you can do to facilitate the hatching of your eggs. If the female hermit crab releases the eggs in the salty water after 30 days and they hatch. There are zero chances for zoea to fully develop. 

Hermit crab zoea will only survive in the ocean and not in captivity. Even if you provide enough salty water for them to deposit their eggs, there is no way the eggs will hatch. And on the chance they do, the hatchlings won’t survive.

Here is why:

The larval hatchlings must remain in the ocean for up to 3 months before they are ready to molt and become juvenile hermit crabs.

If you want to test if you can be lucky, try simulating the ocean and beach ecosystem.

Wrapping Up – Do Hermit Crabs Lay Eggs?

Hermit crabs do not give birth, instead, they lay eggs. Unfortunately, you might not see these eggs develop into baby crabs as they will rarely survive. The only way hermit crab eggs will survive is if they are deposited in the ocean.

Frequently Asked Questions About Hermit Crab Eggs

Can my hermit crabs have babies?

Yes, if you have provided the right conditions to your hermit crabs, the female can lay eggs that will she will release in the salty water after 30 days. However, the chances of these zoea surviving are very low. I have only seen two people who have succeeded in breeding hermit crabs in captivity and only 2% of the thousands of the zoea survived.

How do you make a hermit crab have babies?

If you want to try breeding hermit crabs in captivity, start by making sure you have a female and a male. Then provide the right environment and conditions. If the female and male mate, the female will lay up to 50,000 eggs that will hold onto her abdomen for 3o days. She will then release the eggs into the salty water so that they can hatch. To try and see if the zoea will fully develop, recreate the ocean environment.

How do you know when a hermit crab is pregnant?

Your female hermit crab is pregnant if you notice lumps of brick-red circular balls attaching to her abdomen. Since the abdomen is always hidden in the shell it’s rare to notice when she has eggs. If you see your male and female mating keep checking inside the shell to see when the eggs develop.

Can you put male and female hermit crabs together?

For a female hermit crab to reproduce, it must mate with a male hermit crab. So you should have both genders if you want them to lay eggs.

What do mating hermit crabs look like?

The female and male will first come out of their shells. Then they will bring their stomachs together and it will look like they are fighting. Mating happens in the water.

What are baby hermit crabs called?

Newly hatched hermit crab babies are called zoea. The zoea then goes through six stages to develop into a megalopa. The megalopa then finds its first mollusk shell and will start spending more time on the land. They will then bury in the sand to molt and will eventually develop into juvenile crabs.

Do hermit crabs come out of their shell to mate?

Yes, they will come out partially or fully outside their shell to mate. Mating happens in salty water.

What should I do if my pet hermit crab lays eggs?

There is little you can do. The only thing you can do is recreate the beach and ocean environment. The zoea stays in the salty water for up to 40 days until when they can find their first mollusk shell and start spending more time on land.

How long is a female crab pregnant for?

The fertilized eggs stay attached to the female’s pleopods for 30 days before they are released to hatch into the salty water.

How many baby hermit crabs are born/hatch at once?

How many babies do hermit crabs have? A female hermit crab lays thousands of eggs, sometimes as high as 50,000. How many baby hermit crabs fully develops depends on the environment. The few people who breed hermit crabs at home report only  2% to 3% of the zoea fully develop. Hermit crab babies are not born, they hatch. 



Simon Griffiths

Hi guys, my name is Simon, a fellow pet lover. I love everything about traditional and exotic pets so I am here to help you create a better home for your pets.