We’ve all seen them. The cages on the boardwalk or in tourist shops throughout our town. The cages filled with sometimes hundreds of hermit crabs with pretty painted shells, waiting to be sold in a small cage. It doesn’t seem like such a big deal, right? Parents buy the crabs for their kids, expecting it to die soon anyway. People are attracted to the cutely decorated shells and the seemingly ease of taking care of a small crab. However, there is a much bigger story behind the small crabs. The maintenance, care, and even the industry they come from all have their importance and flaws.
If you already have a Hermit Crab
Usually, you’ll see signs and offers for a free hermit crab with the purchase of a cage. Firstly, the cage being small isn’t the only issue with this. Ironically, hermit crabs are social animals, meaning they need at least one other hermit crab with them. In the wild, they have little herds, with up to around 100 crabs! This is not only beneficial for the social aspect of the crab, but also for the pack. When the crabs outgrow their shells, they can pass it down to a smaller crab, and so forth.
Moving onto the cage itself now, they are often lacking in the things these crabs need to live. The ones sold at the boardwalk (and other tourist shops) are very small, have no substrate and are not kept at a constant temperature. While these cages might be okay for transporting your crab home for very short periods, they should not be kept in those cages for long periods. It’s recommended that hermit crabs have an at least 10 to 20-gallon tank so that there can be a temperature gradient. But cage size also depends on the number of crabs you have, and generally larger is better. A full-grown hermit crab is larger than a softball and requires a 75-gallon tank!
Importance of Substrate
Crabs will need something called a substrate. The substrate is the material they will be sitting on, digging through, and even hiding in. There are different kinds of substrate you can get for your crab, but some are better than others. The substrate is extremely important for hermit crabs, though sadly, many of the shops that sell hermit crabs keep them in a big cage without anything but water and food.
Without substrate or substrate that isn’t deep enough, crabs cannot molt, which means they can’t shed their exoskeleton. When crabs need to molt, they bury themselves underground, in complete darkness so that ecdysone (or the molting hormone) can be secreted. After they shed their exoskeleton, they are very vulnerable. They cannot move until they harden up again, meaning without the protection of the substrate, another hermit crab might try to eat it. The substrate must be at least three to four times deeper than the size of their shell. While they are going through a vulnerable time, the substrate keeps them hydrated and insulated.
What Substrate to Get?
There are a few different kinds, but the best is what they would find in their natural habitats, which is a mix of moist soil and sand. A lot of crab owners use a mix of sand and coco fiber, which helps retain the humidity in the tank. Sands and fibers that are natural, but also sanitary are best for hermit crabs. Don’t use any soil or sand that has been dyed, treated with chemicals, or otherwise tampered with. When you buy or mix your substrate make sure to moisten it. The consistency should be like the sand you can build sandcastles with, not too wet or dry. This is so that the crab can dig and burrow without the sand collapsing on top of it.
You can get a little spray bottle with water in it so you can spray water on the substrate when needed. Also, certain types of substrate can attract bugs or fungus, but you can’t use a pesticide to kill them! Since hermit crabs are arthropods, and therefore related to bugs, they’ll die if exposed to pesticides.
Humidity and Temperature
To keep Hermit Crabs alive, humidity is one of the most important things to consider. Hermit Crabs have modified gills, which helps them to breathe air, but they are still gills. Hermit Crabs need at least 70% to 80% humidity in their tanks. Too much humidity is also harmful though because, above 85%, mold will develop. You will need to purchase a humidity gauge so that you can ensure that their humidity is at a safe level.
The temperature also needs to be kept above 75°F, but letting your crab get too hot can result in irreversible damage and death. You can keep the temperature around 75°F by getting an under tank heater or light. One side of the tank should be warmer than the other, that way crabs can heat up and cool off as they please. Getting a thermometer for the tank makes sure that you’re maintaining the right temperature much easier.
There are a few ways to keep the tank humid for your crabs. Getting a natural sponge and soaking it is an easy and effective way, but the sponge needs to be natural and hermit crab safe. Having a couple of sponges to switch out is also effective, that way you can clean and disinfect one sponge while another is in the tank. However, natural sponges can be expensive and if they don’t get cleaned regularly a new one will have to replace it.
Cage Accessories are very important to the crab and even its life. Land Hermit Crabs love to climb and climbing is a great form of exercise for them. Choya or Cholla wood is a good option but pieces of driftwood or coral are good too.
Another thing hermit crabs need is extra shells. There should be 3-4 extra shells for each crab, so they can choose which shell they like the most when they grow.
Hermit Crabs will also need two types of water, freshwater, and saltwater, so two bowls will be needed. The water should be deep enough so that they can soak, but not too deep that they drown. Certain species can have deeper water though, so make sure to identify the kind of Hermit Crab you have.
For food, some people use shallow shells or bowls that aren’t too deep. If a scum or gross looking film develops at the bottom, make sure to wash it out. It’s oils from their food, and they don’t need any extra.
Hermit Crabs can be fed many things since they are omnivores, but the little pellets from the pet store aren’t recommended. They can eat meat, fruits, veggies, nuts, seeds, and more. Keeping things fresh will make it so that commercial crab food isn’t necessary. Crabs have further nutritional needs so it’s important to keep track of what you feed them.
Why NOT buy hermit crabs
If you don’t already have a hermit crab, please do not buy one, especially from stores like Petco, Petsmart, and the tourist shops in Ocean City. If you are interested in getting a hermit crab please rescue one from someone who had one and doesn’t want it anymore. A video from PETA showed the environment that the crabs were forced to live in after they’d been captured. Now, I’m not a PETA supporter, I think they’ve done more to hurt animal welfare than help it, but when there’s video evidence showing how cruelly the crabs are treated, it’s difficult to dismiss it.
Since Hermit Crabs can’t breed in captivity, they are taken from the wild. After the crabs have been captured, they’re put into a big cage. In the cage are thousands of other hermit crabs, and little to no food or water. The floors are flat and hard, which means they have no place to dig and hide. After that, the crabs get their natural shells crushed and get a painted one. Even if the paint is non-toxic, if the paint flakes off and the crab eats it, it could kill them. When the crabs have access to water, it’s not the proper kind and it usually comes from the tap. The Chlorine found in tap water is harmful to them.
Please do not support the Hermit Crab Industry. Usually, a kid or young teen gets the hermit crab, but they don’t know how to take care of them so they usually die a few months later. Hermit Crabs should not be souvenirs for tourists or a ‘starter pet’. Hermit Crabs require much more care than what it seems and can be expensive to care for. Even though it’s “just a crab,” it doesn’t mean they should have to face a life of negligence.
This is not an extensive guide
This isn’t an article on how to care for your crab. I’ve included the basics but there is so much more to caring for a Hermit Crab. Please do your research if you have one already and give your crabs the best life possible. If you don’t have any please don’t buy any crabs.