Care Guide: Land Hermit Crabs
Living Care Information
Coenobita clypeatus
Commonly known as hermit crab,
Caribbean hermit crab
Quick Start Information
Do not mistake your new hermit crabs for unhealthy or dead if they aren’t moving much when they first arrive. This is normal and expected behavior due to their long trip.
Hermit crabs are about 1 to 2 inches long. They can have shells of all different shapes, sizes, and colors.
About the Organism
- Hermit crabs are nocturnal.
- Hermit crabs communicate with one another by making croaking or chirping sounds by rubbing against their shell or rubbing their body parts together.
- Hermit crabs mate in the ocean. Before mating, the male holds the female with one claw, and then taps or strokes her with the other. Both crabs emerge partially from their shells and place their stomachs together to mate.
- A female hermit crab carries fertilized eggs attached to her abdomen until they hatch.
- Hermit crab larvae are aquatic and go through several developmental stages in water before making a permanent transition to land.
- Some land hermit crabs can live up to 10 years.
- Domain: Eukarya
- Kingdom: Animalia
- Phylum: Arthropoda
- Class: Malascostraca
- Order: Decapoda
- Family: Coenobitidae
- Genus: Coenobita
- Species: clypeatus
Preparation
Hermit crabs can survive in their shipping container for a couple of hours, but we recommend that you take them out of the shipping container immediately and place them in their new habitat.
Housing
Land hermit crabs are best kept in a large, dry container such as a terrarium or an aquarium with 10 to 15 cm of sand or clean wood shavings in the bottom. Each hermit crab should have a gallon of space. Consider our terrarium habitat kit if you need a complete setup for your hermit crabs.
The terrarium should mimic the crab’s natural habitat as much as possible. Cover the bottom of the terrarium with sand (children’s play sand, which beach sand has rounded grains, works best) or a sand/humus mixture. We also offer a suitable sand substrate.
If the sand is 8 cm or deeper, the hermit crabs can burrow, which they like to do, especially before molting. Lightly moisten the sand to provide the humidity that the crabs require. Add a shallow bowl of water and branches, rocks, or other items as desired. Metal dishes should be avoided as hermit crabs are extremely sensitive to metal. Use a ventilated top.
There should be a hiding place for each crab. Keep only crabs of similar size together, as larger crabs may dominate smaller crabs. A small branch or piece of driftwood can be added for the crabs to climb on, but the container should be large enough so they cannot climb out. A small dish of fresh, conditioned water should always be available. Dry moss or crumpled paper towels can be added to one side of the terrarium for the crabs to burrow under, especially during times of molt when the crabs must leave their shells.
It is critical to keep land hermit crabs warm. They are tropical and will die if exposed to temperatures below 10° C (50° F). The crabs are most active at temperatures between 22° C and 27° C (72° F and 81° F). At temperatures below 18° C (65° F), all activity stops. If your hermit crab seems lethargic or stops moving, check the temperature. In a covered container, a 25-watt light bulb will usually give off enough heat to keep the crabs warms.
Additionally, maintaining a humidity level between 70 and 90% is important. Keep water bowls less than 2 cm deep so the crabs will not drown. Hermit crabs keep a small amount of water in their shells so their gills will remain moist. Water should always be available. If you don’t keep a bowl of water in their habitat, remove the crab from the habitat once or twice a week and place it in a bowl of conditioned water at room temperature. Mist the terrarium daily, increasing ventilation if mold appears.
Feeding
Hermit crabs are omnivores. Dry food, pieces of apple or other fruit, lettuce, toast, and cookies are acceptable options. We offer dry food, which is an easy method for feeding.
A vegetable diet is preferable because uneaten meats spoil or mold. In captivity, hermit crabs do not eat large quantities of food; feeding once or twice a week should be adequate. Do not be concerned if food is not immediately eaten.
Maintaining and culturing
At the time of molting, a hermit crab needs a source of calcium to assist in the hardening of the new exoskeleton. A few pieces of eggshell placed in the terrarium will usually meet this need. As the crab grows, it will need to move into a larger shell. Several shells of different sizes should be kept in the terrarium so the crab can change homes as necessary. Any of the spiral gastropod shells are acceptable, but keep in mind some types of shells have more interior room than others.
Disposal
Carolina provides living organisms for educational purposes only. As a general policy, we do not advocate the release of organisms into the environment. In some states, it is illegal to release organisms, even indigenous species, without a permit. The intention of these laws is to protect native wildlife and the environment.
We suggest that organisms be:
- Maintained in the classroom.
- Donated to another classroom or science department.
- With parental permission, adopted or taken home by students.
- Donated to a nature center or zoo.
- Disposed of humanely, as a last resort.
Hermit crabs can be chilled to immobility and then frozen. After being frozen for a few days, they can be thawed, sealed in plastic bags, and disposed of.
Biosafety
Wash your hands with soap and water before and after handling any organism as well as after cleaning its habitat.
Video
No video or video playlist applies for this organism.
FAQs
How many hermit crabs should I keep in a terrarium?
A 10-gallon tank or terrarium can hold 2 small to medium-size hermit crabs. Keep crabs of similar size together, as a larger one may bully or even eat a smaller one.
How long will my hermit crabs live?
The ages of your hermit crabs are unknown. They will likely live for several months. Given adequate space, food, and clean water, they could even live for years.
What can I do to ensure that my hermit crabs live for a long time?
Keep their habitat humid. We suggest both a thermometer and a humidity gauge in the terrarium. Watch for mold, clean the terrarium regularly, and keep food and water fresh.
Why aren’t my hermit crabs moving?
Check the temperature in the terrarium. The crabs will become inactive if they are too cold. Also, hermit crabs are nocturnal animals and are most active at night, when they can be noisy.
Will my hermit crab grow?
The crab will, but its shell will not. It’s a good practice to keep several shells of various sizes in the terrarium for the crab to move into. Sometimes hermit crabs will reject the shells if they have cracks or holes. This could be because the crab keeps a small amount of water in its shell to keep its gills moist, and if it leaks, the crab could die. Crabs may also reject shells that contain sand or other materials.
My hermit crab came out of its shell and won’t go back in. What do I do?
This is often a sign of stress; try to determine what is causing it. One common cause is high temperatures. Have you been using a heat lamp? Is the terrarium in direct sunlight? Look for unsanitary conditions and check the shell to see if it has cracked. Also, remove any metal objects. Place the crab and its shell in a clean, soap-free glass, bowl, or cup that is just large enough to contain the crab and shell. In such proximity, the crab will probably reenter its shell. If not, give it a slightly larger shell.
My hermit crabs have mites! What can I do?
Vacuum the crab’s habitat, wipe it down, and rinse with plain water. Let it dry in the sun. Replace the bedding. Boil all accessories, water dishes, and extra shells for at least 20 minutes. You can also bake any oven-safe items in an oven at 300 degrees.
To remove the mites from your crabs, you will need to clean each crab in a bowl of room temperature, dechlorinated water. Place your crab in the bowl of water. Turn your crab upside down to get all the air bubbles out of his shell. Then, pour the water off your crab into the bowl. The mites will drain off your crab along with the water. Pour the mites and water down the drain of your sink. Do this once more or until all the mites on your crab are gone. Make sure there are no mites in your crab’s shell.
You can also use a paper towel to squish any of the mites on your crab gently and carefully. Draining, wiping, and rinsing your crab will help remove the mites.
If you have tried the plain water cleaning method and the boiling method, and still have mite infestation, you will need to use a mite-specific medication for hermit crabs. You can get this medication from a vet that specializes in arthropods or from an exotic pet supply store. Check crabs for mites daily and repeat the process if necessary.
Need help?
We want you to have a good experience. Orders and replacements: 800.334.5551, then select Customer Service. Technical support and questions: caresheets@carolina.com
