Did you know that one of the main staples in a wild hermit crab's diet is feces? I know, pretty gross huh? But it makes sense. Hermit crabs are beach combers and as they travel across the beaches and the inland areas they consume all sorts of things and animal and bird feces make up a large part of that. The practice of consuming feces is called coprophagia.

Since I started crabbing every great once in awhile I hear stories of a crabber introducing some sort of feces in their tank. Turtle, guinea pig, and horse poo are the ones that I've heard of. The crab responses are usually very good.

Recently too, the practice of adding worm casting to the tank has become popular. Worm castings are basically a clean dirt but no less than 100% worm poop for it. Few people think of worm castings as true feces because it is honestly what makes up the dirt in your yard, but it provides much of the same benefits.

After some late night internet combing however, I ran across a product I'd never seen before, Seabird Guano. (Guano is a polite word for bird/bat feces). I passed on the bat guano because I couldn't see crabs venturing into cold, dark caves however, seabird guano is something that they would certainly encounter in their natural environment.

So did they like it? No word yet. As the weather shifts they've got all got underground as they normally do for a few weeks. I'm going to be doing a deep clean and installing some warming cable and I'll be back to update you on how it's received in a few weeks.

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The following is the raw results from a hermit crab survey that I set up over the course of one month. I invited crabbers from lots of different forums to participate and we had, in the end, over 300 participants. While this is a great number, more than I had hoped for, keep in mind that it's not a perfect sample. It's a sample of crabbers who are willing to go online to read about, research, and talk about crabs. There is still a significant demographic of crabbers who don't do that.

1. How many crabs do you have?

2. How many active tanks/crabitats do you have (not counting ISO)?

3. Do you have a tank specifically designated for ISO situations?

4. What is the size of your largest tank?

5. How many species do you have?

6. What type of substrate do you use?

7. What type of heat do you have? (check all that apply)

8. Do you have a thermometer?

9. Do you have a hygrometer? (measures humidity)

10. Do you offer salt water?

11. What do you use to make your salt water?

12. Do you use stress coat dechlorinator?

13. Is your substrate moist or dry?

14. What kind of fresh water do you use?

15. How many times a year do you deep clean your tank?

16. Do you bath your hermit crabs?

17. Have you ever adopted a crab rather than buying it at the store?

18. As a general rule, do you let your hermit crabs molt in the main tank or do you ISO them?

19. Have you ever purchased food/items from an online hermit crab specialty store?

20. What kinds of food do you feed your hermit crabs? Select all that apply.

21. How old are you?

22. Are you male or female?

23. How long have you had hermit crabs?

24. How long have you had the crab you have had the longest?

25. Would you consider yourself a hermit crab activist?

Survey written and executed by LolaGranola, feel free to post and reference on your site or blog. A link back to Naturally Crabby is appreciated but not required for this post.

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10. Crab Foods Should be Chopped Up Into Tiny Pieces

I see it all over. Recommendations and descriptions that talk about dicing crab foods up into tiny crab-bite size pieces. The only hermit crab that needs their food made very small is a crab that is missing both of it's pinchers or if the food is very very hard to break into pieces. Hermit crabs come fully equipped to disassemble all manners of foods. It's the biological duty! In addition to that they have very few activities to do in the tank so don't deprive them of the opportunity to sit and pick a big hunk of apple or walnut apart. It makes eating an action oriented activity rather than just a set of motions. Food in large chunks also allows them to detect exactly what they are eating without being confused by several ground foods mixed together.

9. Crabs Prefer Painted Shells

I've seen this stated in several different places, however not one of them could point me to an article or study that proved that this was true. It's certainly a convenient statement to justify selling painted shells to unsuspecting parents. Not only do crabs not prefer painted shells, the methods used to get crabs into them are cruel at best. In what amounts to nothing more than a cheap marketing ploy to get children to try to talk their parents into an impulse-pet-buy, painted shells are one of the last approved methods of animal cruelty allowed in pet stores. Click here to read a longer article about painted shells.

8. Commercial Food is an Adequate and Complete Diet

This is another common myth perpetuated by the petstore industry and some others. Commercial food is problematic for a number of reasons. First it often contains harmful additives and preservatives like copper sulfate and ethoxoquin. Additionally, even healthy crab diets are not complete (even if they state that they are). Hermit crabs require variety, they are biologically imprinted to move to different foods every 12 hours or so. Offering them the same manufactured foods over and over will cause them to lose interest and deprive them of the true variety that they need.

7. Gravel is the Best Substrate.

In truth, gravel should be nowhere on your acceptable substrate list. There are people who use limited amounts of gravel under the water dish but using gravel as a general substrate is a bad idea. It's impossible to dig and bury safely in, it's often painted, and it's easy for bits of gravel to make it into the shell of your crab, injuring their soft abdomen.

6. If Your Hermit Crab is Sick, Put Them in the Dark

Hermit crabs are very dependent upon the natural day/night light cycle to regulate their metabolism. If you have a sick crab, give them a hiding spot, like a coconut hut but do not remove them from all light or cover their tank with a towel. The light/dark cycle will help their bodies work as they were meant to and will increase their chances of getting better. This is especialy true for treating Post Purchase Stress.

5. Hermit Crabs are Exclusively Nocturnal

It's true that hermit crabs in the wild are most active at night with the heat of the sun and visibility to predators making the day time much less hospitable. Hermit Crabs in captivity however are much more active during the day than their wild counterparts. The longer they live in captivity the more comfortable they will be coming out during the day. Be careful not to let the nocturnal argument be an excuse for why your crabs are never out and active. A healthy crab will have periods of activity even if you miss them. A crab that sits in one spot and never moves has a problem that needs to be addressed. This problem is almost always improper humidity and temperature as well as a limited access to fresh and salt water.


4. Crabs Can't Have Pools of Water or They Will Drown

This myth never made sense to me but I hear it over and over again. New crabbers are given the solemn, serious advice that they must not, under any circumstances, allow their crab near standing water. In fact, many go so far as to advice you to only offer your crab a damp sponge! This is terrible advice on a number of levels. First, crabs are beach dwellers, they come from the land of big water. They're more then equipped to handle a 1 inch water bowl. Second, crabs need to get water into their shells. This requires you to provide a pool of water at least deep enough to reach your largest crab's shell opening. Not only will theny not drown, they love water. Throw that sponge away, you don't need it. Get them a pool and some natural moss instead!

3. You Should Mist Your Crabs Regularly

There's no reason for you to squirt your crab with water unless it is suffering a serious health problem and you are concerned for it's shell water level. If you are trying to raise your humidity, mist the inside walls of your tank. Crabs generally don't like to be misted. There are some exceptions, I had a crab, Ol'Grandad, who use to run out whenever he realized I was on mist patrol. I would mist the area next to him and he would walk into the spray and stretch out, getting the water all over his armor plate. He's the only one though. Maintaining proper humidity and providing pools does the job that you are trying to do by misting. Put. the spraybottle. down.

2. Crabs Don't Live Very Long

This is a lie and it's one that often ticks me off. Instead of providing proper care instructions, many pet stores hand you your crab and your stuff and when you come back a few months later to ask why your crab died, the answer is . . they don't live very long, a few months to a year at most. It's an easy lie for us to believe. Hermit crabs are small. Other small critters have relatively short lifespans, it's not that far out side the realm of believability. However, hermit crabs have an incredible life span. Easily 30-50 years in the wild. That large crab you brought home last week is probably older than you are! This has been confirmed in the wild and domestically as Carol of Crabworks two crabs, John and Kate, are over 30 years old!

1. Crabs Don't Need Salt Water

This one is the most common and often the most deadly. Hermit crabs (every species) needs salt water to regulate the salinity of their shell water (this keeps their gills and abdomen moist) as well as to aid in their molting and their metabolism. This must be ocean style salt water, not table salt, commercial sea salt (for cooking with) but salt that is designed to be used to set up a salt water aquarium (it doens't have to be filtered sea water like in the picture, any sea mix will do). If you don't have salt water in your tank, go buy some salt and set up a pool, observe their reaction. Most crabs will drink the water and soak in it for several days after the initial offering. It's an absolute must for all hermit crabs.

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One of the most popular searches that brings people to Naturally Crabby is a variation on "how do I take care of my crab that I brought home from the beach." Now there are two possibilities here. 1. Someone purchased a hermit crab at a boardwalk tourist trap and is looking for basic care information (believe it or not this is the better option of the two). or 2. Someone picked a hermit crab up off of the beach and took it home.

I can completely understand how tempting it might be to take that little fellow who you've been interacting with all afternoon home to live with you. He is cute, quirky, and very very active. There are a couple of major problems though. The first problem is that harvesting hermit crabs (even one) is illegal. You must have a special permit to harvest them. This allows the USDA to keep track of their numbers so that the ecosystem does not become unbalanced. You might say that one crab doesn't make a difference, but imagine 1000 more people thinking the same way that you do. Put that crab back!

The other reason that bringing home that beach crab is a problem is because the odds are overwhelmingly against that crab being a Land Hermit Crab. In North America, Land Hermit Crabs are confined to a very few specific locations. So what are you finding out walking about on the beach during your vacation? Why Marine Hermit Crabs of course! They are notorious for scurrying around in the tide pools looking for food.

Below is a picture of a marine hermit crab, look at the differences between this one and the land hermit crab at the top of the page. The eyes are a big give away, as are the lack of a big pincher!

Here's why bringing home marine hermit crabs is a huge problem. Marine Hermit Crabs MUST live completely underwater in a fully cycled salter water aquarium complete with live rock. They will absolutely die if they do not have this setup. What's worse is that they will die a slow suffocating death as their gills will allow them to live for several days but they just aren't efficient enough at processing air to work much longer than a few days.

So let's say, hypothetically, that you already brought one home. What do you do? First choice is to take it back to the beach ASAP. And by beach I mean the ocean beach where you found it, a body of fresh water won't work. If you are too far from the beach you only have a few other options. You must work fast, because time is running out.

First determine whether or not you are willing to fork over the money required to set up a salt water system for these little guys. If not move on to step two.

Step two, get on the phone, start calling mom and pop, locally owned pet stores that have salt water fish tanks. Explain that you accidentally brought a marine hermit crab home from the beach and have nowhere for it to go. Large pet chains rarely will agree to take them because technically it is illegal, although you can try. The smaller stores are more likely to take pity on the poor thing.

If everyone says no, start calling schools and universities and ask if they have a biology department, talk to anyone that might know if they keep tanks and what kind. You must not wait to do this. You can prolong his life a little by offering dechlorinated salt water with a bubbler in it. But it is not a permanent solution.

In the end, the best thing you can do is just to leave the hermit crab on the beach where you found him. Take some good pictures to remember your trip and if you really want a new hermit crab, adopt one when you get home.

Speaking of Jumbos, I went down to St. Louis to visit Daethian from All Things Crabby and we had a great time. We ended up going to Petco and checking out their hermit crabs. They had a strange mix of Jumbos, large crabs in painted shells, and small crabs in natural shells. I got a couple of jumbos including Lewis.

He's been injured and is missing his left armor leg as well as having a huge chunk nicked out of his walking leg. He still uses it pretty well though. As you can see he is also coming up on pre-molt pretty desperately by his cloudy eyes.

I thought it was funny that I picked up a jumbo (who is now easily the largest crab in my tank) right after I wrote the article on Jumbo crabs. Ah well, I maybe change the pictures in the article eventually.

Lewis has gone off to hide as I expected. I'll just try not to hold my breath as I wait for him to come out. He sat in the water dish for several minutes without moving. It was like he was in a trance. I snapped this picture before he seemed to come around and wander off. I could just imagine him thinking . . . ahhhh, pooooool.