Need help ASAP understanding crab behavior

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Crabster5
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Need help ASAP understanding crab behavior

Post by Crabster5 » Sat Dec 07, 2019 9:21 pm

Help...I am concerned. We had five crabs but they'd go to molt and never return so ultimately we were left with one that has been alone for quite some time. We decided to move it to a new crabitat and we did that today, and we decided also that it needed friends. At the pet store we picked up three new crabs, two smaller ones and a bigger one. I probably should have read up about how to introduce new crabs but last time we did it everything was fine so I didn't anticipate any problems. At the pet store they put the three new guys in a box and we rushed them home trying to keep them as warm as we could since it was cold outside. We put them into the new tank by the side heaters to warm up. The two smaller ones just lay there looking nearly dead but the bigger one ran off to explore and our original crab (Hermie) seemed very aggressive with him, like he was pushing him into the corner and the new guy seemed traumatized and kept getting rolled over on it's back, but honestly, neither my husband nor I feel qualified to judge crab behavior. It may just be that Hermie was surprised or excited to see another crab after so long but in the back of my head there's always the nagging question as to whether or not Hermie killed our other crabs. I immediately became concerned about the little crabs who are so much smaller than Hermie so ultimately we decided to just pull Hermie out and put him back in his old crabitat to seperate them. He seems bewildered and confused and we don't really want to have two crabitats to tend to, plus all I have left are some shallow pools from early on and the deeper newer ones are in with the little guys so I'm worried about them possibly drowning. Should I try reintroducing them tomorrow? What does aggressive behavior look like? We'd be totally traumatized if Hermie were to hurt or kill any of our new ones. Any advice would be so appreciated, I'm getting ready to go out of town on Monday. Thank you!

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Harry Wang
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Re: Need help ASAP understanding crab behavior

Post by Harry Wang » Sat Dec 07, 2019 10:04 pm

Apparently if you place them in the freshwater pool, it will give them the scent of your other crabs. A short act of dominance is common when introducing to a tank.

I’d bet your crabs are either moulting or destressing - had a similar scare for a few months but most of mine eventually resurfaced. Honestly I haven’t been separating them when they moult as some might suggest; it’s impossible to keep track of for me. Just keep em fed and hope they aren’t all like “whelp Zoid, there’s plenty to live on over there but I’d rather eat you buddy.”

Mine are all PPs but I’ve read that Ecuadorians tend to be less friendly towards moulters. Good luck!

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Re: Need help ASAP understanding crab behavior

Post by Motörcrab » Sat Dec 07, 2019 10:04 pm

Sometimes it is best to dip your new crabs in your dechlorinated fresh water before adding them to your tank. It helps them to smell more familiar.

Your other inactive guys sound like they are suffering from PPS. Post Purchase Syndrome is similar to a depression. Here is a link for more info on PPS. There is a lot of helpful information and what to feed them to get them out of the funk.
http://www.hermitcrabassociation.com/ph ... 27&t=92531

It is hard to say what type of behavior Hermie was showing. He could have been trying to steal the other crabs shell. That looks like one crab is trying to piggy back on the other. Be sure you have at lest 3-5 shells for each crab. Be sure they are only slightly larger than what each crab is currently in. You need to measure the inside diameter of the shell opening. With smaller crabs in 1" and under shells I usually give them shells 1/8 to 1/4 inch larger than what they current wear. Larger crabs I usually go with 1/4 increments.
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Hermiesguardian
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Re: Need help ASAP understanding crab behavior

Post by Hermiesguardian » Sat Dec 07, 2019 10:42 pm

I question why all your other crabs died. Are the crabitat conditions correct? Heat/humidity, substrate depth, consistancy, diet.
raising son's dog, Dante. Husky/hound.
Raising daughter's hermit crabs, Shelder, Paras and Derek. Added 2 more of my own (of course) Pete and Stryper. Former mommy to 2 guinea pigs and beloved cat, Nissi

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Re: Need help ASAP understanding crab behavior

Post by curlysister » Sat Dec 07, 2019 11:30 pm

I was also wondering what your conditions are like, and how long the previous crabs have been 'gone molting'.

Harry - The HCA does NOT recommend separating crabs to molt. They can and should be left in the tank with the other crabs. If all conditions are proper, they can safely molt in there.
"If there are no dogs in Heaven, then when I die I want to go where they went." -Will Rogers


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Crabster5
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Re: Need help ASAP understanding crab behavior

Post by Crabster5 » Sun Dec 08, 2019 10:37 am

Hello thank you for all your information! Very helpful. I too wonder why the others all died, it was really heartbreaking. In all honesty it's a lot of work taking care of crabs and my daughter had gotten one as a present in a little tiny plastic container and the person said they were really easy to care for. I realized how much is involved after researching it. I'd gotten two friends for it at the pet store and another two from Craigslist and the lady who had them said they weren't fun and didn't do anything and she had them living on a half inch of aquarium gravel so clearly a lot of people out there don't know how to care for them properly. They had successfully molted but then next time around they went down and never returned and it's been a year so I'm sure no one is coming back. With the new ones, I'm realizing that one of them is dead and at the pet store there weren't a lot. I'd seen this one tucked into it's shell and thought it was just hiding but there's been no movement, I think he got stuck somehow or it seems like he's almost glued in there. I think he was actually dead at the store and I just couldn't tell. I feel awful for it. The smallest one is gone this morning so I'm assuming it's dug down for the night or maybe is molting already? I will look into getting more shells, the bigger ones seem harder to find and two of mine are on the bigger side, but I found a website. I will try the pool dipping method to see if that works. Thank you all!

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Re: Need help ASAP understanding crab behavior

Post by Hermiesguardian » Sun Dec 08, 2019 11:15 am

Crabster5 wrote:
Sun Dec 08, 2019 10:37 am
Hello thank you for all your information! Very helpful. I too wonder why the others all died, it was really heartbreaking. In all honesty it's a lot of work taking care of crabs and my daughter had gotten one as a present in a little tiny plastic container and the person said they were really easy to care for. I realized how much is involved after researching it. I'd gotten two friends for it at the pet store and another two from Craigslist and the lady who had them said they weren't fun and didn't do anything and she had them living on a half inch of aquarium gravel so clearly a lot of people out there don't know how to care for them properly. They had successfully molted but then next time around they went down and never returned and it's been a year so I'm sure no one is coming back. With the new ones, I'm realizing that one of them is dead and at the pet store there weren't a lot. I'd seen this one tucked into it's shell and thought it was just hiding but there's been no movement, I think he got stuck somehow or it seems like he's almost glued in there. I think he was actually dead at the store and I just couldn't tell. I feel awful for it. The smallest one is gone this morning so I'm assuming it's dug down for the night or maybe is molting already? I will look into getting more shells, the bigger ones seem harder to find and two of mine are on the bigger side, but I found a website. I will try the pool dipping method to see if that works. Thank you all!
That's wonderful you adopted crabs from horrible set ups. What are your conditions? How big is your tank? Humidity, heat, substrate...?
raising son's dog, Dante. Husky/hound.
Raising daughter's hermit crabs, Shelder, Paras and Derek. Added 2 more of my own (of course) Pete and Stryper. Former mommy to 2 guinea pigs and beloved cat, Nissi

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Re: Need help ASAP understanding crab behavior

Post by DragonsFly » Sun Dec 08, 2019 4:45 pm

Crabster5 wrote:
Sun Dec 08, 2019 10:37 am
Hello thank you for all your information! Very helpful. I too wonder why the others all died, it was really heartbreaking. In all honesty it's a lot of work taking care of crabs and my daughter had gotten one as a present in a little tiny plastic container and the person said they were really easy to care for.
Yes, it is a lot of work, and a lot of expense, frankly, to do it correctly (even if you DIY everything you can). And, no, they are not easy to care for--that is a lie. They are only "easy care" if you don't mind that they die in a few days/weeks/months. Also, they are terrible "pets" for children, because they are not pets at all, but wild animals abused into captivity that require very specific and tricky-to-create conditions in order to survive, are nocturnal (so your child will likely see them seldom if at all), and throughout their lifetime will spend weeks, months, and eventually years at a time underground molting, during which time their conditions must be maintained although you will not see them at all. Not to mention that they might live 20 or 30 years if you DO keep proper conditions--and what kid is ready to make a decades-long commitment like that? Marvelous "pets" for kids. :roll:

As to why the others died, it's certainly possible that this was just "post-purchase syndrome," which means that they were so injured/traumatized by the processes of being abused into captivity that they simply could not survive. The estimate is that over 99% of crabs "harvested" from the wild and abused into captivity will die within the first few days or weeks no matter how they are kept. But, if you think you do want to continue in crab-keeping, it is well worth carefully studying all of their requirements to see if there is something lacking in your current "crabitat" that needs to be improved to increase their chances of survival. Best wishes!
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Keep a good thought--they're rare these days.


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Crabster5
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Re: Need help ASAP understanding crab behavior

Post by Crabster5 » Tue Jan 07, 2020 8:11 am

Hello again, I guess I'm just a worried crab mom. So I had the large crab, Hermie, and then got him three friends, whom I'll just call Medium, Smaller and Smallest to make it easy. Hermie seemed a little aggressive (or maybe he was just excited to have friends) so I removed him the first night before bed because I was anxious to leave them unattended overnight. The new guys all disappeared that night so I figured they are molting. After awhile we returned Hermie to the crabitat with the new guys. My husband did see Smallest a couple of weeks ago but not since then. Medium was also out but only briefly. Smaller has been out a couple of days now but I keep finding him upside down and not moving. My husband said he saw Hermie turning him over (and once looking like he was trying to pull him out of his shell so he quickly moved Smaller) and it seems like Smaller can't right himself. I keep picking him up and setting him leg-side down but find him awhile later upside down. Unless I stay there by the tank and watch I can't tell if Hermie just keeps knocking him over or if Smaller just falls over on his own. He doesn't seem to make any attempts to do anything but lay there and I can't tell if he's sick or just being submissive or if he figures "why get up I'll just end up on my back again so why bother?" I am wishing I'd kept Hermie's old crabitat, I sometimes wonder if he misses it, I keep finding him in corners looking like he wants out and he didn't use to do that in his old digs. I'm not sure if they get attached to their crabitats or not. Advice about Smaller would be very helpful. Thank you.

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Re: Need help ASAP understanding crab behavior

Post by DragonsFly » Sat Jan 11, 2020 4:25 pm

So much information is needed in order to know what might be going wrong. The crab that is constantly being found on his back is not a great sign, but it could be that he is ill from poor conditions or has been injured by Hermie or keeps being bullied by Hermie (possibly for his shell?).....

Things we would need to know:
how big is your crabitat?
how deep is the substrate, and what is it made of, and how moist is it?
what is the temperature and humidity measured in the tank?
how many extra shells do you have in the tank, what kind are they, and how big are the OPENINGS of the shells, compared to the kind of shells and opening sizes of the shells that the crabs currently have on?
what do you feed the crabs?
do you have two water sources, one for fresh water and one for Marine Salt Water (made with a mix sold for Marine Salt Water fish), both deep enough for the crabs to submerge in?
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Resident PP's:"Major Tom" "Billie Jean" & "Mr. Jones"
Keep a good thought--they're rare these days.


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Crabster5
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Re: Need help ASAP understanding crab behavior

Post by Crabster5 » Mon Feb 03, 2020 4:22 pm

Hello, I'm sorry I didn't answer all the questions before, I've been away working on my parents' house. I returned a few days ago and my husband told me that Smaller was running around without it's shell but that it was fine. At one point he found it riding on Hermie's back and he assumed Hermie had brought him up from a wide open hole he was at the bottom of. I was worried about Smaller but was horribly exhausted and went to bed and the next morning Smaller was down in the hole not moving. He hasn't moved for days. We brought him up out of the hole so that we could cover him with a plastic cover (like we saw on a website--to protect the crab from other crabs since we thought maybe Hermie is bothering it when it's trying to molt.) It hasn't moved for a few days at all so we figure it has died. It does not smell at all though so I am wondering what's going on, I know it's easy to mistake molting crabs for dead crabs and I don't want to make a mistake here. When we emptied out our old crabitat that Hermie came from we never saw any crab parts so don't know what ever became of the four who'd gone to molt and never returned. We don't know if Hermie ate them or they just decomposed. Should I leave the crab in there even though I think it's dead? When will I be sure it's dead? Should I wait for the smell?

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Re: Need help ASAP understanding crab behavior

Post by curlysister » Mon Feb 03, 2020 4:31 pm

A crab will go without a shell when it is too weak to carry it. Usually it is because something is not right in the conditions/ water/ food. We can help trouble shoot with more information; you can copy and paste the 'emergency' template if you would like.

Is the crab in a shell now? If it has been naked for days and now not moving for days, unfortunately it does not sound good.
"If there are no dogs in Heaven, then when I die I want to go where they went." -Will Rogers

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Hermiesguardian
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Re: Need help ASAP understanding crab behavior

Post by Hermiesguardian » Mon Feb 03, 2020 4:33 pm

Crabster5 wrote:
Mon Feb 03, 2020 4:22 pm
Hello, I'm sorry I didn't answer all the questions before, I've been away working on my parents' house. I returned a few days ago and my husband told me that Smaller was running around without it's shell but that it was fine. At one point he found it riding on Hermie's back and he assumed Hermie had brought him up from a wide open hole he was at the bottom of. I was worried about Smaller but was horribly exhausted and went to bed and the next morning Smaller was down in the hole not moving. He hasn't moved for days. We brought him up out of the hole so that we could cover him with a plastic cover (like we saw on a website--to protect the crab from other crabs since we thought maybe Hermie is bothering it when it's trying to molt.) It hasn't moved for a few days at all so we figure it has died. It does not smell at all though so I am wondering what's going on, I know it's easy to mistake molting crabs for dead crabs and I don't want to make a mistake here. When we emptied out our old crabitat that Hermie came from we never saw any crab parts so don't know what ever became of the four who'd gone to molt and never returned. We don't know if Hermie ate them or they just decomposed. Should I leave the crab in there even though I think it's dead? When will I be sure it's dead? Should I wait for the smell?
I'm sorry but he's probably gone. A crab cannot survive without their shell. They dry out. They need to be reshelled within a couple of hours. If a crab leaves his shell like that it's because he's too weak to carry it. A molting crab doesn't leave its shell. You really need to fill out completely the emergency template so we can see if your conditions can be improved upon. You haven't answered anytime we asked about your conditions.
raising son's dog, Dante. Husky/hound.
Raising daughter's hermit crabs, Shelder, Paras and Derek. Added 2 more of my own (of course) Pete and Stryper. Former mommy to 2 guinea pigs and beloved cat, Nissi


Topic author
Crabster5
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Re: Need help ASAP understanding crab behavior

Post by Crabster5 » Mon Feb 03, 2020 7:27 pm

That's too bad, the last thing we ever want to do is to be causing the deaths of these sweet little crabs. I will work on filling out the information and post it here tomorrow. I regret not having done this sooner.


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Crabster5
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Re: Need help ASAP understanding crab behavior

Post by Crabster5 » Tue Feb 04, 2020 6:56 pm

Hello again, I believe we have a 20 gallon tank. Our substrate is about 4-6" deep, made up of 5 parts sand to 1 part ground coconut fiber. It's moist but not too moist and we spray it daily. The temperature is about 70-76 degrees with about 80% humidity and there are two 9 watt heaters on each side in a back corner for warmth overnight (we don't leave the heat light on at night, we turn it on and off during the day). I think we have about 10+ shells but several are buried. I'm not sure what kind they are. Our crabs are all different sizes so it's a mix and we really don't have measurements. We feed them food from Petsmart (river shrimp and a calcium powder supplement) and also fresh fruit and veggies and some peanut butter. They have both fresh water and salt water pools which I think are deep enough, though I worry about getting anything too deep because I am afraid of the smaller ones drowning. That being said we have constant problems with our pools in that the water starts leaking out of them after some time, does anyone know what causes that? Are the crabs' claws poking holes in them? We have a mesh screen top and put dish towels over it and vinyl placemats on top to keep the humidity in. When we have the light on we drape it around the light. Thanks for any feedback.

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