Territorial/ Aggressive Crab ?

[breanne_angel]

Hello everyone, this might be a long post so strap in.
So, about a year or so ago I did experiments on hermit crabs for a science class and ended up giving two to my friend. Over the course of the past year, one of them ended up killing the other while he was molting and so the other one has been alone since.
My friend is moving so i decided to take the crab back and also get him some roomies as I knew from the extensive research that they were social creatures. Before we get to that part though, a few days after bringing the original crab home he was out and about, drinking and eating but then one day he crawled into this little coconut hut I had for him and he hasn't left for DAYS. At first I thought he might've been surface molting and I made sure everything in his tank was perfect, humidity, heat, food, etc. I ended up increasing the humidity a little which made him more active but still not leaving the hut. and there was no signs that he was leaving the hut at night either, no sand in the water dishes or the food dishes. no tracks . nothing. he just paces around the hut. burrows a little maybe. thats it.

I was going to try to address this issue first, but then my two other crabs arrived so I threw them in the tank as I don't have the room/equipment for an isolation tank. They seem perfectly fine, happy, and healthy and both immediately took to exploring the crabitat. The original crab didn't really seem to mind until one of them went into the coconut with him. Thats when he started attacking the other crab. So i pulled them apart and turned the hut around for a little while so he could settle down and the other crab could politely find a different hiding spot in the tank.
Ive since turned the hut around again and put a small piece of wood in front of it as my original crab is a solid golf ball size and the other two i just got are about the size of marbles. I do believe they're all PP tho.


So, im asking several things.

1) Why do you guys think the original crab likes the coconut so much ? is it stress from moving him from my friends enclosure to another ? I will admit, my crabitat does need a few more good hiding spaces so I wouldn't be surprised if thats it.

2) Do you guys think the original crab was just being territorial over the coconut and that once he gets out into the open crabitat he will become less aggressive or should I be preparing to try and find and set up a solo tank for him ?



I know people will usually then ask people to fill out the "emergency section" questions so very quickly
- its a 20 gallon tank with a mixture of play sand and coconut substrate. id say maybe 60:40 towards coconut substrate.
- the humidity and heat are both kept at a MINIMUM of 80 but sometimes during the day increase slightly, maybe to like 85.
-both fresh and saltwater dishes are kept out for them, no sponges in the dish
- a variety of fruits, leafy greens, and smelly fish have been provided when he was active but for the last day or two i just threw some pellets my friend had left over in there cause it was obvious he wasnt eating
- theres like 8-9 shells in the tank right now, all turbos. most of them are for the original crab but two are the size of the new crabs. I don't think thats a cause for aggression as they're very different sizes.



also as i was writing this the original crab came out of the coconut so i will try to update this post on the behaviors. Thanks !!

if theres anything else im forgetting to mention

[breanne_angel]

A slight update: the original crab left the coconut, went into the freshwater dish for a minute and has since begun burrowing under said water dish. The other crabs are both inactive in two other places of the crabitat (one on a climbing wall and another under a tree branch ) so he hasn't really had an interaction with either of them since the incident.

I will give another update tomorrow morning probably (unless someone replies, of course)

[SnipSnapDad]

I saw similar behaviour in one of my bigger crabs when I first added my coconut hut. He instantly claimed it and became very territorial and it took a few days for him to calm down. Much like you experienced, he eventually wandered out and stopped being as crazy after a few days. Hoping it works out with his new friends!

[JoeHermits]

Having more hiding places and cover would be helpful. Since they're a primarily inland species vulnerable to predation they feel less secure out in the open.

But yes, moving him to the new enclosure could be causing stress, just because it's new and he's not used to it.

Many people have found some success dipping everyone in the freshwater to make them all smell similar. Having protein and calcium (cuttlebone or egg shells) available can also help since those are needed most for molting and sought out by new crabs in survival mode.

[breanne_angel]

I saw similar behaviour in one of my bigger crabs when I first added my coconut hut. He instantly claimed it and became very territorial and it took a few days for him to calm down. Much like you experienced, he eventually wandered out and stopped being as crazy after a few days. Hoping it works out with his new friends!

Thanks I actually had the exact same experience. He got over it the next day or two and now all of them are burrowed within a few inches on each other. It's quite cute actually so it seems to be going well so far.

[breanne_angel]

Having more hiding places and cover would be helpful. Since they're a primarily inland species vulnerable to predation they feel less secure out in the open.

But yes, moving him to the new enclosure could be causing stress, just because it's new and he's not used to it.

Many people have found some success dipping everyone in the freshwater to make them all smell similar. Having protein and calcium (cuttlebone or egg shells) available can also help since those are needed most for molting and sought out by new crabs in survival mode.

Thank you ! I saw the freshwater advice a few times on here after making this post but I didnt get around to trying it. But I've since added calcium and protein and a lot more hiding spaces to the crabitat and now have three very happy (i hope) burrowed crabs .
I do appreciate you responding to this post though, thank you from a semi-new crab owner who is trying to do everything right.