Hermit crabs are fascinating crustaceans that are popular as pets, for various reasons. Despite having an interesting name and appearance, hermit crabs are said to be intelligent and friendly too. They do not need much space and are easy to maintain. These crabs are less prone to diseases and are free of any offending odor. Usually, they are not found to cause any allergies and so, are ideal for people with such medical conditions. However, you have to provide them with some basic requirements that include optimal temperature and humidity settings and an ideal substrate. Let us take a look at the various aspects of pet hermit crab care.
How to Care for Hermit Crabs
Biologically, hermit crabs do not show the typical characteristics of 'true crabs.' These crustaceans are characterized by a soft abdomen, which is protected with the shells of sea snails, inside which they live (unlike true crabs). So, as they grow, owners of pet hermit crabs must offer larger-sized shells, corresponding to their growth. Basically, these crabs are omnivores, which mean they feed on both vegetation and animal material. There are marine and land hermit crabs and usually, the latter type is considered good pets.
Choosing the Right Pet
Coenobita clypeatus and Coenobita compressus are the two main species of hermit crab, found in United States. Coenobita perlatus and Coenobita variabilis are the other two species found in other parts of world, besides the previous two types. Although, land hermit crabs are relatively easier to find, you have to be careful while choosing your pet. They have five pairs of legs, among which three pairs are generally found to be well-developed. Usually, they display three pairs of legs and you have to make sure that all pairs are present, when you buy one. You should also check the shell, whether it is intact or not. The crab should not be dull as it is an indication of its unhealthy status. It should be free of parasites and offensive smell. If you are adding one to your previously maintained stock, then make sure that the new arrival is having a matching size. It will be better to contact a pet store that specializes in these pets. Make sure that these crabs are maintained well. As they are social animals, get them in pair or groups.
Housing Hermit Crabs
The actual habitat of land hermit crabs is regions with warm tropical climate. Hence they require a warm, humid environment in the tank to survive. They do not require huge homes, but maintaining an optimal temperature and humidity is absolutely important for their survival.
The Tank: Hermit crabs can be housed in tanks made up of glass or plastic. Although, the tanks are available in numerous sizes, normally, an aquarium having a capacity of 10 gallon with a sliding glass lid is the preferred choice. Don't go for bigger ones, as a 10-gallon tank offers the needed room for cage furnishings and sufficient space for the movement of the pet.
Substrate: Although there are a couple of other options, sand is the most commonly used substrate for hermit crabs. As burrowing is one of their natural habits, sand provides a good means for such activities. Aquarium sand or playground sand is a better, easily available and inexpensive option. It is better to sterilize it by rinsing, drying, or baking. Such sand can be re-washed and used again. You can also get some calcium-based sand, which comes in a variety of colors, but are quite expensive.
Fiber bedding made for reptiles is another good option for substrate. Bedding made up of coconut fiber (called forest bedding) is mainly used for this purpose. The fiber is grounded fine to have the feel of soil; hence it is good for burrowing. Crushed coral also makes a fine choice, but then you should provide an area with forest bedding or sand as this is more preferable substrate for your pet hermit crab, especially during molting. Avoid the use of wood shavings or gravel bed.
Temperature: As mentioned earlier, hermit crabs are from hot tropical climate and they enjoy a temperature of 72 to 80° F (22-27° C). Hence, the use of heaters to keep crabs at this optimal temperature becomes a necessity. Undertank heaters and lights or a combination of both can be effectively used to maintain the required temperature. Undertank heaters (UTH) should be used with thermostat for a better temperature control.
Humidity: As far as keeping pet hermit crabs are concerned, you have to maintain optimal levels of humidity in the tank. Since their respiration is via gills, they require proper amount of oxygen which depends on the humidity factor in the air. A humidity of around 70 to 80% is sufficient for these crabs. So, it is better to install a hygrometer in the tank. Excess humidity is also not advisable, as it stimulates the growth of bacteria and fungus in the tank. The water dish you introduce in the tank is sufficient for maintaining the proper humidity, as long as the tank is enclosed. Introduction of natural sea sponge also helps the cause of increasing humidity.
Cage Furnishing: Proper cage furnishing is another important aspect of pet hermit crab care. There are certain basic requirements like stuff to climb on, food dish and a water bowl. Cholla wood is ideal for climbing activities. Drift wood or coral pieces can also make a good option. You may keep some artificial plants for furnishing the cage. Try to change them periodically to bring variety in the tank. Some people keep extra shells for the crabs. These shells can be used by these crabs, as they grow.
Feeding Pet Hermit Crabs
In the wild, land hermit crabs eat almost anything like fallen fruit, leaf litter, decaying wood, plants and grasses. Although, they are not specific in their diet, recent studies have shown that hermit crabs need calcium, carotene and antioxidants. You can witness the fading in their color at the time of molting if their diet is carotene deficient. You can supplement their diet with brightly colored vegetables like corn and carrots to make up for the deficiency of carotene.
You can feed them with meat, fish, vegetables and fruits as they are omnivorous. They also like tannin-rich foods like tree bark and oak leaves. Wash and then dry these fruits, prior to feeding. If you can offer your pet with a diverse diet of 'human grade' food, then commercial crab food is not at all necessary. You can pick up these foods from your nearby grocery store. Provide them with fresh (and dechlorinated) water in a shallow dish. Make sure that the water does not contain any chemicals or impurities.
Hermit Crab Molting
Molting is the process during which your pet sheds off their skin and grows a new one. During molting, hermit crabs are under a lot of stress, and hence extra care is required. Usually an isolation tank is the best solution. You can shift the particular crab in altogether different tank or in the temporary cage made in the parent tank, though latter is always a better option. Avoid extra handling as these will only add to the stress. Leaving them alone is always the best way to take care!
The above said is only a brief overview about the various aspects of pet hermit crab care. You must try to gain a sound knowledge about these animals, if you intend to get them as pets. For this purpose, you may approach the local pet store or a person, who is already having hermit crabs as pets.