Keeping the Land Hermit Crab in Captivity
The Land Hermit Crab, (scientific name Coenobita clypeatus)
is also called the Caribbean Hermit Crab or the Tree-
Climbing Hermit Crab. They live on the sub-tropical sandy
beaches of Mexico and the islands of the Caribbean. These
crabs choose empty shells of other sea creatures for
protective homes, and lodge their bodies inside the shell so
that all you can see of the actual crab is the legs, claws
Hermit Crabs make entertaining, interesting and fairly
easily kept pets. Somewhat unfortunately they are often sold
during the summer at venues other than pet stores, such as
in shops on recreational piers or the like, so they may be
impulse purchases and the buyer may have no idea how to care
for them. Whether you are carefully deciding whether to keep
Hermit Crabs as pets or you have suddenly become the proud
possessor of one or more of these funny creatures, here are
some facts and tips to make the experience a success for
both you and the crabs.
Your Land Hermit Crab Tank
Your Hermit Crabs will need a tank that approximates their
warm tropical shoreline home. For two crabs you'll need a
tank of about eight inches by twelve inches, and eight
inches high (twenty by thirty by twenty centimeters). Tree-
Climbing Hermit Crabs are gregarious and it is best to keep
at least two crabs. You will see much more interesting
natural activity that way and your crabs will be happier as
well. You can keep a colony of up to twenty crabs if you
provide a large enough tank.
For a substrate it is recommended that you buy from your pet
supplies shop the special calcium-rich sands sold for
reptiles. They not only are clean and free from parasites,
but they hold moisture, are easy for your crabs to dig in,
can be washed and reused, and help to provide necessary
calcium for your crabs. Lay down a sand substrate of four
inches (eleven centimeters) at one end of the tank and
tapering to two inches (five centimeters) at the other end.
Your crabs will dig a burrow in the sand for a hiding place
when frightened or molting.
As you can see from the name "Tree-Climbing Hermit Crab,"
your crab tank will also need some wood and/or cork bark on
which to climb. Both you and the crabs will enjoy the tank
more if you make it attractive, so decorate a bit with
interesting driftwood and rocks from your pet store.
Environmental Conditions for Hermit Crabs
Since they come from tropical or sub-tropical lands, your
Caribbean Hermit Crab tank will need to be kept between
sixty-nine to eighty degrees Fahrenheit (twenty to twenty-
four degrees Celsius) at all times. The easiest way to do
that is to buy a heat mat from your pet store and either
place it under two-thirds of the tank bottom (to allow the
crabs to regulate their temperature by moving from the
warmer to the cooler end as needed) or mount it to the
backside of the tank. You might want to also purchase a
stick-on thermometer of the type commonly sold for reptile
tanks so you can check the tank temperature on an ongoing
basis. Be sure to leave the tank set up with the heat on for
a day or so to monitor the temperature before you add your
crabs. You don't want to cook them.
The next consideration is the moisture provided for your
hermit crabs. Their bodies (the part hidden in the shell
they have chosen for a home) are soft and must be kept
moist. Under natural conditions the surf and tropical rain
take care of that, but in your home you will need to help
them with this or your crabs may suffer or die.
Once a week, put lukewarm water (Let tap sit for a day or so
to allow the chemicals to disperse.) in a bowl. Pick up a
crab, holding it so the shell opening is upward, and dunk
the crab into the water so that the shell fills up with
water, then pull it back out of the water and drain out the
water. Dunk it again and leave it there until the crab
starts to leave its shell. At that point pull it out of the
water and put it back into the tank. Do this with each crab.
Feeding Hermit Crabs
Coenobita clypeatus are omnivorous. Try feeding them not
only commercial hermit crab food that will help to supply
needed vitamins and minerals, but also small bits of
vegetables such as carrots, peas, and tomatoes, dried
shrimp, fruits such as banana, apple, mango or peach, and
maybe even a few bits of dog food. Be sure to feed them only
small bits at a time, and remove all uneaten soft food from
the previous day to prevent mold and help keep the tank
clean. Some experts recommend an occasional small bit of
honey with vitamin/calcium supplement added to help keep
their exoskeletons strong.
You will also need to provide a water dish about one inch
(three centimeters) deep for every couple of crabs and of
course keep them clean and filled with aged tap water or
other de-clorinated water.
Crabs, like other crustaceans, must shed their exoskeleton
as they grow. (At molting time they also regenerate any
missing legs, which is a handy gift.) Land Hermit Crabs
normally molt every twelve to eighteen months. Just before a
crab begins to molt, the legs and claw will change color to
orangey and possibly also develop yellow spots. If you see
this, it is good if you can move the molting crab to a
private tank, preferably with a higher level of humidity, as
the crab is very vulnerable during the molt. Also be sure to
add several extra water dishes because crabs must drink a
lot of water during the molting process.
When a Hermit Crab molts it also will move to a slightly
larger shell to accommodate its larger size, so you should
provide several shell choices for your crab. You can provide
natural shells you have found or purchased, or even the
fancy painted shells you can buy at some pet suppliers.
While your crab is molting it will dig down into the
substrate and hide. You might want to use deep sphagnum moss
for the substrate of the molting tank, rather than sand, to
make it easier for the crab. Once the crab begins to molt,
don't disturb it until the process is finished, or the crab
Take good care of your crabs, and they will reward you with
plenty of entertainment as they climb around the tank and
interact with each other, grow and change shells, and give
your home the feel of a Caribbean beach.
Crabs & Invertebrates as Pets