aggressive crab

[krabby kristen]

i have a particular crab who has been aggressive towards the other crabs at times and especially aggressive towards the new crab i just got that is a bit slow moving still.
i am wondering if there is any way to help this problem. it's been ongoing for a while now and last time i posted someone said they need more protein so i bought them a protein mix and started feeding them more hard boiled eggs.

i'm getting frustrated i would like all my crabs to live in peace lol
so i am up to any advice or suggestions
thank you

[MudCrabDude]

i have a particular crab who has been aggressive towards the other crabs at times and especially aggressive towards the new crab i just got that is a bit slow moving still.
i am wondering if there is any way to help this problem. it's been ongoing for a while now and last time i posted someone said they need more protein so i bought them a protein mix and started feeding them more hard boiled eggs.

i'm getting frustrated i would like all my crabs to live in peace lol
so i am up to any advice or suggestions
thank you

Honestly, I've yet to come across surefire way of predicting individual crabs' behaviors in captivity, much less a method to make sure they live peacefully together in a closed tank, regardless of size or diet or numbers or if they are new in a tank or not or if they are newly molted or not.

Personally, I myself would just try to learn to accept their ways as is, being the "crabs" that they are. At this point in time, there really is little I could do about it if I were in your position - which I have found myself countless of times before - short of just trying to keep them separately in individual tanks and/or having closely monitored every time they come in contact with each other.

In your current situation, I would just try to separate the newbies if there are any seemingly violent encounters, such as one crab trying to remove a leg or pincher of the other crab. If it is a shoving match or a crab just climbing on top of the other's shell without actual pinching of the crab's vital parts (legs, eyestalks, pinchers, etc.) I would generally just leave them be to let them try to learn to recognize and to get along with each other.

I would be at the top of the world whenever I find my current pair eating peacefully or just sitting together without a shoving match breaking out (which happens more often than not, I'm afraid). With my remaining two, I'd just roll with the punches at the very least, and at most, try to break apart seemingly violent fights if it comes to that (which has not happened yet) but also learn to accept that I cannot be there all the time, however, to break up fights that happen, say, under the sand or under the heavy tank decor.

If a fatal fight occurs, then sadly, I've learned how to accept this as part of our current method of crab keeping when more than one individual is in a tank at any one time. I've also learned not to get too attached with one individual crab as well in the past few years - I've seen one too many a crab keeper give up groups of crabs for adoption or sale because his or her "favorite" crab(s) has (have) been attacked and killed by the other crabs in the group. I prepared myself, so to speak, for the possibility that either Carryl, my female, might kill the smaller male, Fenner, or that Fenner might end up fatally wounding Carryl in the future; even though I'm hoping it would never happen, that is just the way it is from my point of view, at least. I've learned to how to be very attached to both of my remaining two, yet at the same time be attached to neither...if that makes any sense........

It just comes with the crabby territory, I'm afraid, and luck may play a big part in finding crabs that are just compatible with each other in captivity, regardless of species or size or male or female. I guess I'm pretty lucky that my two currently seem to be a bit more compatible with each other than my other groups of hermits in the past, especially as each one seems to have managed to adjust their molting in such a way in that they would "take turns" digging under and not having to molt simultaneously.

It must be noted that I haven't had introduced any new crabs for over a year now, and I am not planning on getting any more new ones for the next few years. I really admire the other crab keepers who seem to be better at keeping larger groups of crabs for much, much longer periods of time.

[wodesorel]

I think that part of the responsibility of keeping an animal is to keep it as safe as possible. Not every accident or fight can be prevented, but removing an animal from a situation that is likely to turn dangerous is important in my book. I have a lot of crabs, but I don't expect any of them to ever go on a killing spree. Not many crabs are inherently aggressive to the point where they want to kill another crab. Almost all of the time there are reasons behind the aggressive behaviour, but it can take time and some trial and error to figure out the why.

The first is that the aggressive crab isn't being fed properly. A lack of certain vitamins, minerals, or proteins will send them looking for a food source that fills that void, and an other crab will sometimes be the answer for that. Calcium sources like cuttlebone or eggshell, mineral sources like HCP mineral mix, and protein sources that are close to crab like shrimp or krill can help to give the aggressive crab a better source of what it craves. It can take a month or more if the crab is seriously deprived before the cravings stop, though! A balanced diet of fresh fruits and varied proteins is always a good choice at all times.

Another problem could be that the aggressive crab very much wants the shell that the other crab is wearing. This can sometimes be cured by offering both crabs new shells, and waiting for one of them to change. Once the aggressive crab has found a better shell or the shell being fought over is now free for the aggressive crab to move into then there's no reason to be aggressive anymore.

Crabs can be attacked by other crabs when they are ill or are getting ready to molt. Crabs are opportunistic, so if another crab is vulnerable then it could become a good dinner for the others. Molters can sometimes put out a smell before they go to molt that other crabs find irresistibly yummy. This type of aggression will usually clear up after the weaker crab finishes molting and has gotten a bath to rinse off any residual molt smells.

True crab aggression is when they chase another crab down, flip it over, and try to pull it out of the shell. The one being attacked will almost always chirp in fear, making it easier for us humans to realize something is wrong. You'll find crabs that are missing the lower end of their shield leg, or part of their large claw - both are signs of a crab that was retracted into it's shell when it was attacked.

Normal crab behavior is when they crawl all over each other, knocking each other off balance. They'll smack each other with their feelers, which is most likely a way of communicating with each other. Sometimes they'll even shove eat other with their claws, sending another crab rolling away. This isn't aggression, but just how they act with each other. They're a bit barbaric.

Even when an attack happens and you can't narrow down the reason why, separating out the attacker for a month or two before reintroducing him to the main group can often times be enough to make him behave again. Maybe the aggressiveness is a form of being territorial, or maybe it's just the crab get so lonely in isolation that he craves companionship again and doesn't want to chase the others away by being aggressive. It's worth a shot if you're worried about your crabs getting hurt.