Hermit Crab
Home is a truth you live in. Sometimes it’s an orange
Exoskeleton, shining bright like sunrise, or a place
Right between your dreams and your skin. When you
Moult the past, saying thank you, saying goodbye
In the crashing waves, the breeze will blow and
The water will say: thank you, it’s okay, you’ve grown.
Carry your home with you everywhere: the crab
Reveals this wisdom. Let it guide you through storms
And clear skies. Let home carry you and it will
Bring you onto a new shore, into your own shelter.
Tiffany Morris
Hermit Crab
Hermit crabs can be found within the tide pools of the intertidal and subtidal zone throughout Nova Scotia. They can range in size from a penny to a toonie; the larger hermit crabs can be found up to 299 meters from shore, but the smaller ones are limited to the shallow waters. Despite their name, they are not, in fact, hermits, but very social, and they live in large colonies. In some cases, they can be found sleeping within a pile of other hermit crabs and working together to gather food.
These little guys climb and explore, carrying their shells with them. Unlike other crabs, they don’t grow their shells but they find them discarded from other shell-living animals and make them their home. Finding shells that litter the ocean floor, they must find the right-sized shell that will allow them to grow where they can easily take up residence. When they grow too big they search for a larger shell to use, locating another empty one or finding another hermit crab with the shell it wants. Then more crabs join in, lining up from largest to smallest to exchange their shells at the same time. If shells are limited, multiple hermit crabs will fight over other hermit crab shells or they will use any marine garbage or debris that can serve as a home.
Shells are very important to their survival, since hermit crabs have a soft abdomen that they hide. They also use their shell for protection when they are threatened or scared. The shells also can restrict their growth; once they have no further room to grow they have to find a new, larger one.
Life Cycle
Hermit crabs reproduce depending on the water temperature, but typically in mid-summer, each crab begins to look for a mate. Once a mate is found the male fertilizes the female’s eggs, and the female then carries the eggs on land for a month. After a month of keeping the eggs away from the ocean, they return, allowing the eggs to hatch into the first stage of their larvae life stage called zoea (Z-o-ia). They eventually grow into megalops (Meg-a-lops) and continue to grow until they find a shell and become adults.
The adult hermit crabs have five sets of legs (ten legs total), two antennae and a shell. The adults can live up to 30 years in the wild and can live both in the water and on land breathing oxygen. They can be found in rocky and sandy sea bottoms and seagrass beds, but they tend to avoid muddy bottoms.
Life Style
Hermit crabs are omnivores (oum-na-vors) which means that they eat both meat and plants (just like humans can). They eat whatever they can find from macroalgae to larvae, and through their diet, they play an important role in the ecosystem by acting as the garbage cleaners of the ocean floor.
Hermit crabs are very low in the food chain, preyed upon by larger creatures ranging from fish to snails and even other crabs. They are most vulnerable as they are changing shells. If you find shells with small holes, the holes are caused by moon snails that can drill into the hermit crab shells.
Hazards to Hermits
Hermit crabs look very cute and you might think that they would make good pets. Unfortunately, they don’t survive well in captivity, though they are captured in the wild and sold in pet stores. This puts a lot of stress on the populations as it takes shells and mates out of the community. It’s important to leave all hermit crabs and shells where you find them after you finish looking at them.
It’s also important to decrease plastic pollution, since hermit crabs can mistake plastic caps and containers as shells and make them their home. This increases their vulnerability, and it can affect their health. So take all your trash with you and properly dispose of it, because your little friends will appreciate it!
Tips for handling hermit crabs:
- Always have adult supervision around the seashore.
- Pick hermit crabs up by their shell and place them in your hand.
- Cup your hands together to prevent the crabs from falling off and allow them to relax and come out of their shell.
- Keep your hands close to the ground or water to reduce the distance if they fall.
- Return them to where you found them after you’re done.
Emilie Knighton
