A Brief Background
So a little background, Hermit crabs are crustaceans. And what are Crustaceans? They are a class of creatures with segmented bodies and exoskeletons (external skeletons) of which includes the following animals as well: lobsters, shrimp, and crabs.
And you can find hermit crabs living in land or water. They are also classified as “not true crabs” due to their body not containing or protected by hard shells. Fun fact, they are called “squat lobsters”.
The Habit of Borrowing Shells and Why
Their body only contains soft and exposed abdomens hence they are highly vulnerable to harm and predators.
And to protect themselves from harm, hermit crabs actively search for abandoned shells, they do this especially when they grow in size since they need to be able to fit on the shell they live in. They usually use sea snail shells as a home and protection. And when they find the ‘perfect one’, hermit crabs tuck themselves in and use it for protection and also carry it with them wherever they go and stay.
Another fun fact, why are they called Hermit Crab in the first place. They have this habit of living on a borrowed shell and they will often do this habit of completely retreating into their borrowed shells for protection, hence people thinking that they act like hermits.
They can be also very picky with their shells because they rely on it for protection, so they make sure that they fit perfectly on it.
Offering a Helping “Hand”
Hermit Crabs do fight other hermit crabs for the shells but the ones that live together usually help each other to find new shells. When a larger shell becomes available for occupancy, hermit crabs are known to do this habit – they sort the shells from largest to smallest so that other hermit crabs can choose the best shell for them.
Here’s another cool thing about hermit crabs, they sometimes decorate their shells. But not in a pretty decorative way, they decorate their shells for protection. Sometimes they will carry and use sea anemones as a decoration for their shells because sea anemones are poisonous and predators will avoid them.
And also their name Hermit Crab is kind of ‘misleading since their human counterpart does live alone while Hermit Crabs don’t since they live along with other hundred of species!
The reason why it’s so common for some schools that keep hermit crabs as pets in their aquariums is that they eat algae which helps it to be clean. And also, Hermit Crabs require minimal care and maintenance.
Most hermit crabs are small in size, however, land hermit crabs can get quite larger especially the coconut crab that can grow really large up to three feet long and weigh nine pounds! Imagine that!
The coconut crab is unique in its own way compared to the other hermit crabs, when they outgrow their shell it will grow a shell of its own. Pretty cool right?