Where Do Hermit Crab Shells Come From?

Have you ever wondered where those lovely shells that your pet hermit crab lives in originated from? As a former hermit crab owner, I too had this inquiry, which led me to do some research.

In this article, we will dive into the world of hermit crab shells and explore where they come from. Let us explore this fascinating topic together.

Where do Wild Hermit Crabs Find Their Shells?

Hermit crabs are unique creatures with interesting habits, and one of those habits is their need for special living arrangements – in the form of shells. So, where do these shells that are so crucial to their survival come from in the wild?

Wild hermit crabs have to work hard to find their ideal shell homes. They scour the ocean floor and the surrounding environment searching for empty snail shells or other suitable structures that they can use as their home. The preferred shells for most species of hermit crabs are those of gastropod snails such as whelks, cones, mollusks, and tun snails.

Do you ever wonder how hermit crabs choose which shell to live in? They use their sense of smell to detect whether the shell is occupied or not, and after finding one that is unoccupied, they put their abdomen inside the shell to see if it’s the perfect fit. If the fit is not perfect, the crab may leave the shell and continue its search.

It’s important to note that sometimes, hermit crabs may compete with each other for the same shell. In such cases, the stronger crab will forcefully eject the weaker one from the shell, leaving the latter to search for a new home.

What Types of Shells do Hermit Crabs Prefer?

As we’ve learned, hermit crabs need special living quarters to protect their soft bodies. These creatures not only require shells for shelter, but the perfect-sized shell is essential for their survival. So, what types of shells do they prefer?

Hermit crabs prefer shells that are lightweight, secure, and not too heavy to carry around. They also prefer shells with an opening that can be tightly and completely sealed by their large pincers.

The most commonly preferred type of shell by hermit crabs is the shell of the sea snail species known as Strombus. These shells have a slight curve, making it easier for the crab to retract its abdomen fully. Shells from the Turbinidae and Cymatidae families are also popular choices for hermit crabs.

It’s important to note that not all shells are suitable for hermit crabs. For example, shells with a wide opening or a long, straight shape are not the best choices for hermit crabs, as they leave the delicate abdomen of the crustacean exposed to predators.

Additionally, some hermit crabs may have specific preferences for different types of shells based on various factors such as their species, gender, or age.

Why do Hermit Crabs Need Shells?

Hermit crabs belong to the crustacean family and have a soft, curved abdomen that needs to be protected from predators and environmental factors. A hermit crab’s entire body is not hard and cannot produce a natural shell of its own, which is why they need the perfect shell to call home.

The shell not only serves as an armored protection around the crab’s abdomen but also helps with movement. By holding onto the shell’s interior with its legs and pincers, the crab can safely navigate its surroundings, climb up and down rocks or other substrates, and even dig burrows in the sand.

A hermit crab’s shell also serves as a disguise. They carry their shell everywhere they go, and the hardened exterior makes them look like a snail or other small creature, which can help them blend in with their environment and avoid detection by predators.

Another critical aspect of a hermit crab’s shell is the growth factor. As they grow, their body demands more space, and they need to upgrade to larger shells that can accommodate them. It’s essential to maintain several shells of different sizes in a hermit crab enclosure to ensure they always have a suitable option available as they grow.

How do Hermit Crabs Change Shells?

Hermit crabs need a shell that perfectly fits their body size, and as they grow larger, they need larger shells to accommodate the change in size. But how do they go about changing shells? Here’s what happens.

When a hermit crab has outgrown its current shell and needs to change, it will start by investigating the surroundings for a new, vacant shell. Once a suitable shell has been found, the hermit crab will gradually back out of its current shell and move into the new one.

The process of changing shells can take several minutes to hours or even days. During this time, the hermit crab is incredibly vulnerable to predators, as it’s entirely defenseless without its shell. To minimize the risk of predation, the crab will look for a secluded area to change shells, such as in its burrow or under some rocks.

Additionally, hermit crabs may sometimes engage in shell fights with other crabs over preferred shells. In such conflicts, the crab with the most significant pincers will usually win and stake its claim on the shell in question.

It’s important to note that hermit crabs do not frequently change shells, and they don’t do it lightly. Changing shells is a stressful and energy-intensive process requiring a lot of resources from the crab’s body. In captivity, it’s not uncommon for hermit crabs to reject new shells, especially if they’re forced to change during molting.

Can Hermit Crabs Live Without Shells?

We’ve established that hermit crabs need shells for their protection and survival, but what happens if they don’t have one? Can they live without shells?

Hermit crabs cannot live without shells. Their soft and fragile body needs the protection and support of a shell to survive. Hermit crabs can live in shells that are chipped or broken, but if the shell completely disintegrates, the hermit crab will die within a few hours.

In instances where a hermit crab outgrows its shell and can’t find a bigger one, or its shell is damaged beyond use, the crab will undergo what’s called an “emergency molt.” During an emergency molt, the hermit crab sheds its exoskeleton and quickly grows into a new one.

Emergency molting is a risky and challenging process for a hermit crab, as they’re defenseless without their protective shell. They will typically bury themselves in the ground to avoid predators and undergo the molt.

In captivity, it’s vital always to provide a suitable selection of shells for your hermit crabs to choose from. If a hermit crab in captivity loses its shell, it’s essential to provide it with a new one. A crab without a shell will quickly perish, so it’s crucial to check your hermit crabs often and provide them with the care they need to maintain their shell’s integrity.


In conclusion, hermit crab shells are critical to a hermit crab’s survival and serve as both protection and support. In the wild, hermit crabs depend on finding empty shells or structures to call home, and they have specific criteria for their ideal shell. Many different types of shells are suitable for hermit crabs, but the Strombus shell is the most commonly preferred.

Hermit crabs change shells as they grow, but this is a stressful and energy-intensive process. Hermit crabs cannot live without shells, and it’s essential to provide a suitable selection of shells and check on them often to maintain their shell’s integrity.

Understanding where hermit crab shells come from is a fascinating topic, and I hope this article has provided some insights into these unique creatures’ habits and needs.

avatar Noah
I’m Noah, chief editor at VIVO Pets and the proud owner of a playful, energetic husky (Max). I’ve been a volunteer at Rex Animal Rescue for over 2 years. I love learning and writing about different animals that can be kept as pets. read more...

Leave a Comment

Your email address will not be published. Required fields are marked *