It is not uncommon for new owners to wonder why their hermit crab is hiding. After all, when you get a new pet, you want to be able to see it. However, what many individuals do not realize is that hermit crabs are actually nocturnal, so hiding in their shell or in substrate during the day is completely normal. While humans are asleep at night, hermit crabs will typically be more active, coming out to get food and otherwise having a wander.
Reasons Hermit Crabs Hide
As mentioned above, hiding during the day is normal for hermit crabs as they prefer to come out at night. Nevertheless, there are other reasons they might hide, and one of these is stress.
Hermit crabs are often extremely exhausted and physically stressed by the time they reach their new homes. The process of harvesting these creatures can be quite cruel and many have no access to food, water, or heat on their journey from the ocean to a tank in a pet store. They may be severely dehydrated by the time they get to your home; unfortunately, many die soon after being purchased.
If your new hermit crab is hiding or digging a lot, it could be that it is stressed and is looking for a safe place to hide. If this is the case, you should provide plenty of food and water and try to ensure that the area where the tank is kept is quiet and dark. This will allow your hermit crab the best chance of survival.
If you live in a busy home with young children, try to keep noise to a minimum for a few days until your pet has acclimatized to its new surroundings. Be sure to keep the temperature levels correct – between 80F and 82F at the warm end and between 72F and 75F at the cool end. If the temperatures are too high or too low, the environment will end up being uncomfortable for your pet and could lead to more stress. Also try to keep humidity levels between 70 and 80 percent. To monitor humidity and temperature, you can purchase a good thermometer and a humidity gauge online or from a local pet store. Just for your information, Amazon sells a good selection here (opens in a new tab).
Loneliness is another issue for hermit crabs, who usually live in colonies in their natural habitat. If you have just one crab in your tank, do not be surprised if it starts to hide out more than usual. Most owners report that their hermit crabs are much more active when there is more than one in the tank. If you have just one crab and do not have enough space for another one at the moment, try adding some ‘toys’ to the tank as this may help (think rocks, ornaments, fake plants, etc.).
Hermit crabs will hide in their shell during the daytime as this is when they sleep. They tend to be active at night when their owners are sleeping. Nonetheless, other issues can cause them to hide for longer (even at night). These issues include stress and loneliness. If you are worried that your crab is hiding out more than usual, look for reasons. Check the temperature and humidity levels and add toys to the tank to give it something to interact with. If you are still worried, I recommend contacting your local vet for professional advice.
- Featured Image (A Hermit Crab Emerging From Shell): U.S. Fish and Wildlife Service – public domain
- Pagurus bernhardus Outside Shell: Arnstein Rønning – CC BY 3.0
- Four Hermit Crabs: Drcbc – CC BY 3.0
- Hermit Crabs Fighting Over a Shell: Brocken Inaglory – CC BY 3.0
- Dardanus calidus: H. Zell – CC BY 3.0
- Hermit Crab Retracted Into a Shell: Jerry Kirkhart – CC BY 2.0