Unbelievable ... I sat here last night and wrote a big long piece on molting, and today it's not here!!!
Okay, let's try again.
The information that I found on molting said that as crabs get older, they molt much less. And it also said that if a crab lost a leg, normally they can grow a new one back, but it takes 2-3 molts to get it to the same size as the others .... however, if the crab is older, it might not be able to grow back the limb. Maybe that was the case with your Mike. It also stressed that crabs must not be disturbed before, during and after they molt because they are likely to get serious injuries, again I thought of your Mike. You did say that you moved him to do a water change right after he had molted, and I wonder if he wasn't able to complete his molt and that's why his apron was hanging off slightly, and hence his death. I don't know, just throwing some things out there.
You were partially right, they do need to take in alot of water, because it helps them to expand, and allows them to get out of their old shell, but they do not NEED to be under water in order to molt. In fact, with land crabs, they prefer digging a tunnel, going down deep and molting there. It says that when they are in the darkness of their tunnel they secrete a hormone that causes them to molt. It said that a crab could be down in the tunnel for as long as 8 weeks, but not to bother them under any circumstances.
I also found out that if a crab loses enough appendages, or both it's claws, it can do an emergency molt, so that it's back to form, otherwise it can't defend itself or get away from any predators. All the information that I found on molting was really interesting, I didn't know the little suckers were so complex. It went on to say that before molting, a land crab will start digging, and will stop eating -- again it sounds alot like the behaviour my big guy has been showing. The article went on to say that if a crab can't go down into a tunnel, it will molt on the surface, but that it's very dangerous to do so because when the crab is molting it emits an odour that attracts other crabs, and as it's very soft after molting, it has no way of defending itself and that's when the other crabs can attack and eat it. So you should give you crabs plenty of sand to dig in. In fact, it said that you should take up any unnecessary items from the tank, so they have more space to dig in.
I got to thinking after reading all of that, and I am wondering if my big crab didn't hurt his claw on the big rock that I had in that tank. You can see it in the photos I posted, it's a big heavy rock (must weigh about 15 pounds!) -- the reason I say that is because they have dug underneath the rock, and it has fallen down a bit, and I wonder if it didn't fall onto his claw to crack it like that because he didn't fall that hard when I put them back into the tank. Anyway, I got up this morning and I removed the big rock and the piece of bogwood that was in there. My husband used to keep a snake, so I took the piece of bark-wood and placed it over the hole that leads down into the tunnels, that way it covers over the hole (not all the way obviously, they can still go in or out), keeps light from getting down there, and it looks nice too. I took the other piece of bark and laid it on an angle leaning against the glass, so one of the smaller crabs can go under it and have a bit of shelter. Since the big male is spending so much time down in his tunnel, the two smaller females have been spending more time over in the water part of the tank, on the turtle dock.
I really hope my big guy does molt, because I don't like the look of the injury to his claw, and I would hate to think of him dying, that would really suck because I don't think the LFS that I got them from has them anymore. Oh, I also read that as these RLC's get older, they get less tolerant of each other. In fact, the article I read said that they will kill each other, even if they are male to female. It said that when they are juvenile, they are very accepting of one another, but as they get older they will get more dominant and will kill off any other tankmates. That kind of bummed me out because I am not able to keep more than one tank for them right now. So I hope they don't mature too quickly. It also went on to say that as they get older, they don't need as much water, and the person that wrote the article said he went from having a part land, part water set-up to having a terrarium with just a water bowl. Again, seeing as I've just converted my tank into a part land, part water tank .... I hope they don't changeover too quickly!
So all in all it was very interesting reading about crabs and molting. Funny how something so small can be so interesting and we can learn so much from them.
And it will be interesting to see what happens in the coming weeks. When I took the big rock out of the tank this morning, I looked down and they have really done a job with the tunnels, it doesn't just go down, it goes across the tank as well. Makes me wish I had a bigger tank for them to do many tunnels in, but I suppose mine are lucky when I think of all those that are kept solely in an aquarium set up with no land at all, and no possible way for them to dig a tunnel -- which makes me feel very sad.
Anyway, I will post anything different that happens or any news that I find out.
