My older son, Z, is fascinated by his Grandmother's Hermit Crabs, so naturally, she asked whether she could get him one for his birthday. I agreed, since I was under the impression that they were low maintenance, easy to care for, etc. After we received the tiny crab in a small "critter keeper" 1 gallon habitat I started looking into what I needed to do to maintain the crab. My son named him Mick. (Short for Mickey Mouse.)
Here's what I learned:
They are not a great pet for a beginner.
They are harvested from the wild in tropical climates and their habitat needs to be kept around 80 degrees and 80 percent humidity. Temperature, easy. Humidity, I live in the desert?!
They need friends, don't keep just one.
They need access to fresh and salt water.
They need a larger tank, ideally a 10 gallon tank.
So we went to the store and purchased Mick two friends whom my son named Buzz and Rex. (No Disney obsession in this house.) They were the smallest crabs at the store, but still a bit bigger than Mick. I also secured larger water dishes, moss, a humidity gauge and thermometer, a larger tank, natural coral and rocks for climbing, and some shells.
Here are some pictures of the 3 crabs in the first habitat. I covered the top with plastic wrap (vented, of course) to preserve some of the humidity until I could move them to a more ideal tank.
Mick is at the top of the crab stack in the first picture and next to Buzz on the right of the 2nd picture. Right now, Buzz is wearing a light colored shell and Rex is wearing a green colored shell. If/when they change shells we'll be in trouble.
Mick, the tiny first crab, was a little beat up looking when we received him. He was active and would come out of his shell and walk around for the first day or so. I noticed, though, that his smaller pincher was damaged and that he was missing the segments from the ends of some of his legs. I was assured that this was no big deal, that he probably just got stepped on by a larger crab and would regenerate his limbs.
The next day, before buying Rex and Buzz, I noticed Mick lost his small pincher, the entire limb. It was damaged, so I thought that maybe that's why he dropped it. I didn't know about how they regenerate limbs, or molting, to know that this was probably stress related or that he was sick, not normal (well it is normal for some really stressed pet store crabs).
When I purchased Rex and Buzz, I looked for "friendly" crabs that would come out of their shells quickly when on my hand, and made sure their legs were all there and not damaged.
When I put Rex and Buzz in the habitat Mick seemed to perk up for a while. He came out of his shell, checked out his new buddies, ate, and took a dip in each of the water dishes.
The next day, Mick lost another leg. I had since learned about stressed crabs and molting and now I was starting to worry about Mick. I figured the best thing I could do was leave the poor stressed crab alone and hope for the best. The other two crabs didn't seem to bother him. They seemed healthy and didn't lose any legs. They were climbing everything, and Buzz was digging.
The next day, Mick had moved but he lost another leg. I didn't want to disturb and stress Mick by moving him to the larger habitat so I left all 3 crabs in the tiny habitat.
The next day, Mick was dangling out of his shell (which was under him), next to the water dish. He wasn't moving anything and didn't retreat to his shell when I came near. It was clear, at this time, that he was either dead or about to be dead. I took him back to the pet store where he was purchased and insisted on a refund (not replacement).
At this point I learned:
Pet store crabs are harvested from the wild. (I had no idea and would not have agreed to the crab if I knew.)
Pet store crabs are often forced into different shells.
Pet store crabs are often extremely stressed and lose limbs as a result; if this stressed they typically don't survive.
Boil any shells or natural rocks/coral before putting in the habitat.
Buzz and Rex are doing great. I moved them to the larger tank, only 7.5 gallons, but much larger than their first habitat. They are quite active. I also moved their habitat from the kitchen counter to my son's room, because it is quieter and warmer in there.
Neither of the crabs are visible in this picture. Buzz is in the hut and Rex is between the orange plant and coral/rocks. The water dishes are at the front, with the food dish next to the fresh water, there are 6 shells about the same size to slightly larger for the hermit crabs to change into. There is moss in the back left corner for humidity, the crab hut in the back right corner. My plan is to add a second level in the back left for the crabs to have another hiding spot and place to climb. It's hard to tell, but I left a wide section running down the middle of the tank empty so the crabs could just run or walk without hinderance. My substrate is about 1-1.5" of coconut fiber and 3-4" of natural sand. This is deep enough that the crabs can bury themselves under at least 2" of sand. Their shells measure less than an inch wide. I don't have a glass lid, yet, so I put screen over the top of the tank under the hood. I used plastic wrap to cover the holes in the lid. I typically leave the light off because it adds a lot of heat and since I keep the house at 78 degrees normally, it's not necessary to heat the tank more. Winter may be a different story.
