Outside of a home, the odds of a dog interacting with a hermit crab are generally low. So when I met one for the very first time at a local elementary school, I didn’t quite know what to make of it. But I was bent on bringing the classroom pet out of his shell. As it happens, hermit crabs are fascinating little critters—much more than just moving rocks.
Davi: Tell me something about hermit crabs that most people don’t know.
Cayman: I’m not a hermit at all! I’m social and prefer company, and I’m not really a crab in the strict scientific sense. I’m a crustacean.
What food do you crave most often?
Vegetable and plant matter are yummy, but I also like food rich in protein, like krill and lean meat.
Is it true that hermit crabs carry their houses on their backs?
Yes, where we go, our houses go. When our “crabitat” gets too tight, we simply look for a new and bigger home. We won’t occupy a shell that already has someone living in it, though, because that would be wrong.
What happens if you lose a limb?
I may lose a limb due to stress, poor tank conditions or fighting with another hermit crab. If I lose a leg, I might still survive and grow a new one. If two or more limbs are lost, the chances of survival decrease.
Do hermit crabs pinch or bite?
We don’t have teeth so we pinch with our big claw for defense. Don’t mess with us, and we won’t mess with you.
What happens if a hermit crab comes out of its shell?
We generally come out of our shell when our house becomes too small for us and we need bigger digs. We may also leave if there is an unwelcome parasite in our home.
Why does a hermit crab need a shell from another animal?
We are more shoppers than builders. Unlike gastropods, we do not make our own shells, so we are constantly on the lookout for uninhabited shells that are more accommodating to our growing size.
Do you have any special talents?
We can make our muscles shrink to fit into a shell. We are also great climbers and I’m drawn to the smell of the dead because I’m a scavenger.
What are your duties as a classroom pet?
My duties are to be interesting, which is hard to do when I sleep all day. I also have instructions to emphasize my cuddle factor, which is hard to do with a house on my back. And I never come out of my shell unless I’m told.
Are hermit crabs safe to handle?
We are safe if you don’t antagonize us. I prefer to retreat into my shell when I’m picked up.
Do hermit crabs take baths?
We take baths all the time, not just to smell good but mostly to stay alive. We must be kept moist.
Though not all teachers are lucky enough—or brave enough—to have classroom pets, I certainly admire those who do. Classroom pets are a great way to teach students responsibility, compassion and science. No matter which pet is chosen for a classroom, it will surely enrich the lives of the children who get to enjoy its presence. Hermit crabs are no exception.