THIS IS THE COOLEST THING EVER

[DragonsFly]

I have to agree with curly that this is likely not a good thing to happen in captivity. It definitely is happening because "good shells" are a scarce resource (and we humans do NOT know all the things that make a shell "good" to a crab; some that look perfect to us are avoided completely by the crabs). It IS a "cool thing" to witness, for sure! But going forward, I would count yourself fortunate, if "good shells" are scarce in your crabitat for whatever reason, that this happened RATHER THAN shell-related aggression (which we have seen reported more frequently than this). Just a little more pressure (for example, one less "good shell" than they needed, from the crabs' point of view) might result in some crabs harassing, attacking, and injuring others in order to take their shell. Remember that captivity is so completely different from the wild, with respect to all the pressures put on captive animals, that a behavior that is "natural" or "to be expected" in the wild may actually be a "red flag" to see in captivity.

Bottom line: to prevent shell-based aggression, you need to have at least three extra shells PER CRAB, which are the proper type for the species, and in appropriate OPENING sizes (not the same as overall shell size) for that crab (generally one about the same opening size as the crab has on, one a tad bigger, and one a tad smaller). Thanks for sharing this interesting experience!

[Hollym2247]

If it happens in nature, why would you think it’s bad in captivity?


Sent from my iPhone using Tapatalk

[DragonsFly]

As I said, conditions in captivity are hugely different from the wild. This means that behaviors that might be just fine within all the variables of an animal's natural environment may be problematic in captivity.

For one other example, people often cite the fact that hermit crabs can live in colonies of thousands in the wild to bolster the idea that "the more the merrier" in captivity; however, when animals (of any kind) are compressed into hugely unnaturally tiny environments (like almost all captive environments, and certainly the tiny little boxes we keep these crabs in--even if your tank is the size of a whole room, it is still a tiny box compared to an entire island), we know that all kinds of aggressive behaviors increase; in particular, with crabs, more crabs per tank means a geometrically increased chance with each additional crab of aggression over shells or other resources and of potential molting cannibalism.

As I tried to say before, I don't think this is necessarily "bad," I said it is "likely not a good thing" for it to happen in captivity. It is happening in the wild BECAUSE good shells (by crab standards) are always a limited resource in the wild. Therefore, if it happens in your tank, it likely means that good shells (by their standards) are limited in your tank. This likely means that you are very close to the edge of a shell shortage bad enough to potentially cause shell-related aggression.

So, the person whose tank this is should be glad that a "shell exchange train" is what happened INSTEAD of shell aggression; in THAT sense it is "good" that this happened rather than crabs attacking each other for their shells. It can also be considered good in another way: it is a clear sign that more shells are needed, so getting that sign in that way rather than in some other more problematic way is a good thing (and the O.P. is aware that they need more larger-opening shells, and is taking steps to remedy that).

And it is also, as I said, a very cool thing to observe. However, I would definitely not advise wishing for, or in any way working for, having it happen in your own crabitat, because it would at the very least probably be indicating that "good shells" are in short supply, as far as the crabs are concerned, and we know very well that that is a situation in a tank that can cause serious problems, including injury and death.

[pepeto5]

good good










tazones por mayor

[Hermiecrab]

yeah! same