Halloween Crabs F

FAQs on Halloween Crabs (Gecarcinus quadratus)

Halloween land crabs 6/30/14
Hi guys ... have written a few times before about my saltwater aquariums, but this is a new one.
<Fire away.>
Got two Halloween land crabs two weeks ago, placed in a 40 gallon aquarium with lid, 1/3 wet sand and the rest is a pool of distilled water with a filter. Have the whole set up sitting outside under our cabana.
<I see. On the whole, these animals are best kept singly. Do watch them carefully; cannibalism soon after moulting is a real risk.>
Here is middle GA we have a lot of humidity, which has been stable at around 75% and it stays around 85-88 degrees in the shade. (Will figure out a different approach when the weather gets cooler.)
<Indeed. As tropical animals (Pacific coastline of Mexico to Peru) they will need warmth in winter.>
The crabs seemed to be doing fine...there were two separate burrows, food was being eaten and they were getting in the pool of water. (Sometimes eating food in the water.) Anyway, I've been going outside in the evening to catch them eating and getting in the pool and all seemed "normal" from what I know about these creatures, until today when I went out to check on them, their burrows are all covered up. No burrows to be found! Do they cover their burrows up with the sand and if so, will they be able to get
back out?
<Yes, likely so, particularly if moulting. That said, if they're covered by too much sand they might suffocate. Some sands are "stickier" than others and make better burrows. Some crabs will use alternates to burrows if provided, such as ceramic tubes. I had a Rainbow Crab that picked its way
through a huge piece of sponge, and made a pretty neat burrow in that!>
I read they can cover their burrows with leaves, but sand??? (The sand has been kept very moist so it could not have caved in.)
<Ah, that's good; likely the crabs know what they're doing.>
Thanks for your help ~ Linda in GA
<Most welcome. Neale.>
Re: Halloween land crabs 6/30/14
Thanks Neal. One more question, while they are molting, will they come out of their burrows to eat or should I hold off on leaving any food until I see burrows again? Don't want to cause an ant problem in the tank or waste of uneaten food. ~ Linda
<No need to feed. Assuming they are moulting, they'll eat their moult afterwards to recycle the calcium. After that, offering calcium-rich foods (such as unshelled shrimp) will be helpful. Also a source of iodine (like seaweed) would have been a plus beforehand, so worth remembering for next time. Cheers, Neale.>

Halloween Moon Crab - Gecarcinus quadratus 12/8/11
Hi,
I have two g. quadratus crabs - purchased both 12/2010. Keep both together in 20 gal. long with coco fiber substrate, hermit crab sand pile, coco huts/logs to hid in and live plants. Keep moving water fountain and use mister for humidity. Tank temp. ranges 68 - 85, depending on local weather. Humidity at 75% and up. Food offerings are fresh fruit, veggies, hermit crab "cookies", live crickets, shrimp, cooked chicken. Water is declor treated. I have recently noticed that one of the crabs has stopped eating and is sluggish. He still moves around, however, he is not as active.
<Coming up to moulting perhaps?>
Also, he dropped one of his rear legs that seemed damaged at the mid joint.
He is usually the more aggressive crab of the two. What are signs of molting?
<Typically the moult comes off all at once, rather than a pair of legs at a time. In any event, moulting crabs drink a lot, which puffs up their new shell, and then go hide somewhere. Immediately before moulting crabs can feel sloshy if shaken.>
Neither crab has molted in my care. I have also noticed that the crab is taking on more water and that the whitish material under his shell on his backside and alongside his legs is extremely engorged.
<Ah!>
Are those his gills?
<Probably not. The gills are inside the body, underneath the "apron" part of the shell.>
The other day I found him upside down in the fountain. Thought he has died. When I picked him up, he pinched me and spit water at me (why do they spit water?).
<They're cross?>
I could feel water moving inside his shell. I placed him back in tank and now heat tank with 2 75W "moon" bulbs and covered his side of tank with paper for privacy. Crabs are located in very open area. Do I need to supplement with iodine?
<Well, tricky to do with terrestrial crabs. You can get iodine-enriched tablet foods for crabs and these would be good. Otherwise, marine algae is good, e.g., Sushi Nor.>
Should I be adding marine salt to water?
<Not with this species, no, it's a freshwater one I believe. If you wanted to be super-safe, you'd offer one pool of freshwater and one pool of brackish water, and let the crabs choose what they want.>
Have I made this crab sick with improper care?
<Probably not, but do be aware the other crab will likely kill, eat the moulting one.>
Please help.
Heather
<Cheers, Neale.>
Re: Halloween Moon Crab - Gecarcinus quadratus 12/8/11
Neale,
Thank you for such prompt response. I will make arrangements to separate the crabs until this is figured out.
<Sounds wise.>
I will keep the tank dark and limit activities with the potentially moulting crab to just water changes and food offerings. I would think that this will reduce his stress so that he can accomplish a successful moult.
<I agree.>
I will still keep misting with warm water to keep up humidity.
<Good idea.>
I took the fountain out and just have a pool of water (so in case he falls over into fountain, he can flip over again so he doesn't drown). I also have noticed last week that instead of brown poop logs, he was eliminating some sort of greenish-whitish watery goo out of the little chute under his mouthparts.
<Yuk.>
Is there any other signs of moulting that I should be on the lookout for versus having a sick crab..... I will be relieved when he is back to his crabby self again.
<Honestly, there's little to no understanding of crab health, so all you can really do is ensure the right environment, a good diet, and hope for the best. If the crab does get sick, there's nothing at all you can do. We simply don't know enough (anything!) about crustacean healthcare. Moulting crabs tend to be shy and retiring, for obvious reasons, and so we as pet owners see very little of what's happening. But there are not usually odd secretions, so the green goo sounds odd. On the other hand, he may simply have eaten something disagreeable.>
Thanks again,
Heather
<You're welcome. Good luck, Neale.>

Halloween Land Crab 03/17/07 Hi, thank you for taking the time to read this. I have what the pet store called a Halloween Land Crab. <Gercarcinus sp., maybe G. lateralis.> He is not set up in some amazing aquarium, he is just in a plastic cage. I have a water dish for him that's 2 inches deep that he climbs in and out of. The bottom of the cage is filled with calcium sand and aquarium pebbles. <Ideally, he needs a sand substrate deep enough and just damp enough to burrow into, and needs enough saltwater and enough freshwater, each in separate containers, deep enough to fully submerge himself - though the land area is by far the most important.> He has been doing really well eating bits of fruit such as apples, oranges, pineapple and also an occasional guppy. <Needs more meaty foods, preferably things like human-consumption shrimp (raw, frozen and then thawed) and fish; krill, meaty fish foods, and also Nori (seaweed) would be other important foods.> But recently three of his legs fell off on his right side! What is going on? <Likely he is very deficient in something that he needs - saltwater, perhaps, or iodine.... Feeding the foods mentioned above, especially shrimp, krill, and Nori which are rich in iodine, will be very important. Supplementing the food with a reptile calcium supplement will be helpful, as well.> He was not in a fight with another crab and I've never experienced him going through the "shedding process"! Is he unhappy or sick? How can I tell what's going on? <sounds like a state of disease, not a normal molting situation at all.... I would urge you to improve this critter's living space and food.> If this is below what you guys do, then I'm sorry to waste your time, <A question is never a waste of time.> I just need simple answers and can't seem to find them anywhere. <Thank you very much for searching for your answers, and for asking questions.> Nick <All the best to you, -Sabrina>

Land Crab Sickness - 3/7/07 Hi, thank you for taking the time to read this. <Thank you for taking the time to send it!> I have what the pet store called a Halloween Land Crab. <Ah! Gecarcinus sp., maybe G. lateralis.> He is not set up in some amazing aquarium, he is just in a plastic cage. <Really better if he has a slightly damp sandy substrate deep enough to burrow in and sufficient water to completely submerge himself; preferably both a container freshwater and a container of saltwater.> I have a water dish for him that's 2 inches deep that he climbs in and out of. <As long as he can completely submerge himself, this is okay.> The bottom of the cage is filled with calcium sand and aquarium pebbles. <Moist, I hope? And deep enough to burrow in?> He has been doing really well eating bits of fruit such as apples, oranges, pineapple and also an occasional guppy. <He'd do better to have a little more "meaty" food in his diet - bits of human-consumption shrimp (frozen then thawed, uncooked, preferably including the tail or shell), krill, etc.> But recently three of his legs fell off on his right side! What is going on? <Possibly a calcium and/or iodine deficiency.... A diet containing more of these nutrients is important. In crabs that are more aquatic, supplementing their water with these nutrients is very helpful, but in your more land-dwelling Gecarcinus, I don't think it would be beneficial enough to do so.> He was not in a fight with another crab and I've never experienced him going through the "shedding process"! Is he unhappy or sick? <More likely sick, I'm afraid.> How can I tell what's going on? <That's a tough question with no easy answer. Unfortunately, there isn't much information about invertebrate disease. The best we can do for them is to provide them the closest environment to their natural habitat that we can provide. In the case of your crab, this means HIGH humidity, substrate to burrow in, and enough water to totally submerge itself when necessary. I would fear that perhaps the humidity is the problem in this case, as you mention that he's in a very basic setup. A 10 gallon tank or larger with a lid to help keep in humidity would be very good in this case.> If this is below what you guys do, then I'm sorry to waste your time, <There are no questions that are "below" us. Your crab is important enough for you to write in, so it's important enough to us to help you!> I just need simple answers and can't seem to find them anywhere. <There are no simple answers with invertebrate pets, my friend. I wish there were. Try providing him a more humid environment and a diet with more iodine and calcium (again, shrimp with shells, krill - these will be helpful!) will likely be the best things you can do for him right now.> Nick <All the best to you, -Sabrina>

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