Health: What to Do When a Crab Is Attacked

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Health: What to Do When a Crab Is Attacked

Post by HCADirectors » Wed Mar 13, 2013 1:50 pm

A live crab that has been attacked and is missing multiple limbs, or possibly all limbs, is frightening to find, but they can often be saved. Below you will find a summary of the highlights of what to do when you find a crab in this condition. Then below that are links to several members who have gone through this same situation. Once you get things initially under control take the time to read through these posts and learn from those who have experienced similar situations. You should also start your own post about your crab where you can share what happened and ask specifics about your crab.

Initially assess the crab like any other crab in trouble.

Does it have a shell? If not, then getting it reshelled is the first step. If its original shell is available use that, or chose a shell that seems to be the right size. If you are picking a shell, go for one that is lighter weight to allow for better mobility with any remaining limbs. Rinse both the shell and the crab carefully in tank temperature dechlorinated water, then help the crab back into the shell. Depending on the amount of remaining limbs you may be able to try putting the crab and the shell in a glass to reshell itself, but if it has limited limbs it is best to just help it reshell yourself. Carefully back the crab into the shell using your fingers to gently guide the abdomen into the shell.

Safety for the crab

If the crab is missing one or two limbs and is fully mobile on its own, then it may be able to return to the main tank, but that is the exception. Normally these crabs need to be isolated. If the crab is not mobile a kritter keeper placed into an isolation tank may make it easier to prop up the crab where it can reach food and water. It can also go directly into an isolation tank, but should either be in there by itself of completely blocked off from any other crab.

Assess the damage

Can the crab move around by itself? Does it have either claw? Can it hold itself up at all? The answers to these questions will define how you need to care for the crab up until its next molt.


If there was exo left with the crab you should provide that, either as is, or ground up, depending on the ability of the crab to eat. Those who have experienced this have found that calcium and protein are very key to the crab’s survival. If the crab does not have claws, then providing soft or ground up food is important. They can still eat using their mouthparts and can do some level of grinding up food with those. Organic baby foods are one option. Using a mortar and pestle to grind up dry food you already have works well. You can also chop food finely. Using a clam shell often works well since it’s easier for the crab to access the food. You may need to hand feed the crab several times a day. This is time consuming, but also an opportunity to develop a level of trust that doesn’t usually happen between hermit crabs and people in normal circumstances.


The crab will need daily access to both fresh and marine salt water. If they are not mobile you will need to hold them over a shell or dish of water to allow them to drink. Crabs that are not mobile seem to benefit from being put into water deep enough for it to get into their shell and replenish their shell water. Depending on the level of damage and size of the crab you may want to provide water in a clam shell, or small dish. If you place the crab into deeper water to allow water into the shell always monitor this if the crab can’t fully hold itself up.


Providing optimum heat and humidity to these attacked crabs is critical. They are already stressed from the attack and the damage. Try to keep their conditions optimum for the species you have.


The goal for these crabs is to get them to the point that they can molt to regrow their limbs. To do this they will need a variety of quality foods. Once they are near to a molt they will slow down on eating. If they can dig at all they may try to dig a hole. If not, you have to watch for the signs that they no longer want to eat and drink. Once that happens, if they cannot dig a hole for themselves, you should dig a hole just bigger than the crab, place the crab in the hole, then cover the hole with something like a cocohut to make it dark (cover the opening of the hut also). Then you wait.

Member examples of attacked crabs:

Sunshine (owned by Wodesorel)
Small PP ... 07#p755940

Wodesorel found a shell on the surface and a hole, so her instinct was to dig and she found Sunshine freshly molted and naked, with just half a leg and part of her little pincher.

Day 1 - Sunshine was found with under the substrate, freshly molted, and with no shell. She had only one leg and a damaged little pincher.
Day 2 - Sunshine showed signs of eating her exo.
Day 3 - She was stronger and started eating food off of Q-tips that were placed close to her.
Day 14 - Sunshine is showing pre-molt signs of not eating and trying to dig.
Day 17 - Sunshine was moved to a molting isolation tank and covered to make it dark.
Day 24 (approx) - Wodesorel checked on Sunshine since she would be unable to get out on her own if she wanted food or water. Sunshine did drink, but did not eat. She has gel limbs. She was put back in the isolation tank and covered.
Day 38 - Sunshine molted! She was placed back in a false cave with food, include crab exo to replenish the nutrients needs from molting. The false cave was covered.
Day 39 - Sunshine dug under on her own.
Day 47 (approx) - Sunshine came up on her own.
Day 69 - Wodesorel dug down to check on Sunshine. She was in a cave under ground and appears to have molted a second time.
Day 85 - Sunshine is back up after her second molt after the attack.
Day 109 - Sunshine dug down.
Day 137 - Sunshine dug back up, but did not appear to have molted.
Day 163 - Sunshine dug down for her third molt after the attack.
Day 226 - Sunshine is back up from her third molt and is back to normal.

Sparky (owned by CrabbyMom33)
Large Straw ... 67&t=92141

Sparky had been down for a molt and was found on the surface of the substrate with no shell and only portions of his left two legs.

Day 1 - Sparky was found with his right legs and both claws missing, bottom portions of left legs missing, and no shell. Sparky was manually reshelled and set up in a kritter keeper
Day 2 - Sparky has learned to adapt to his situation by using what is left of the remaining legs as claws to bring food to his mouthparts.
Day 7 - Small gel buds can be seen.
Day 37 - Gell buds changed from white to pinkish. Note that the color is likely because Sparky is a straw.
Day 40 - Sparky refused food and took only 2 small drinks of water. He was put in a false cave (hold dug in the substrate) under a coconut hut with the opening covered so it was dark. He was left completely alone for 7 days.
Day 47 - Sparky molted!
Day 61 - Sparky knicked over the shell blocking the cocohut opening and cam out on his own.
Day 76 - Sparky dug down for the second molt after the attack.
Day 99 - Sparky came up from his second molt after the attack.
Day 136 - Sparky moved to the main tank.
Day 144 (approx) - Sparky dug down in the main tank for his third molt after the attack.
Day 239 (1 week short of 8 months) - Sparky came up from his third molt. He finally has legs and claws that are similar in size, but he is still not the size that he originally was prior to the attack.

Bug (owned by CrabbyIrene)
Medium E - unfortunately did not make it after molting


CrabbyIrene saw an orange claw in with a PP that was dug down and left a window by the glass. She dug to investigate and found that Bug had been attacked. She was missing 3 legs, both claws, and some of the little legs that hold them in their shell. The remaining leg was dangling.

Day 1 - CrabbyIrene started hand feeding Bug twice a day.
Day 50 (approx) - Bug has gel limbs and her eating has slowed.
Day 54 - The gel limbs are larger and Bug pushed food away. She was covered to be allowed to molt.
Day 56 - Bug molted.
Day 62 - Bug passed. She did not eat her exo. Her new exo appeared that it did not harden or regain its color.

Fasty (owed by Careyenz)
Medium E ... 27&t=87824

Based on a "gut feel" Careyenz felt like there was a molter in danger and she dug to find Fasty had been attacked. He had 2 legs remaining, not claws, and was still soft from a very recent molt.

Day 1 - Fasty was placed in a Kritter Keeper inside Cayreyenz's 10 gallon isolation tank. He was eating and drinking using a remaining leg as a claw to move food and water to his mouth.
Day 8 - Fasty continues to eat and is getting stronger. No gel buds are visible.
Day 15 - Fasty continues to gain strength and is managing to get around in a 10 gallon tank a bit by himself.
Day 24 - Small gel buds are visible.
Day 27 - Fasty started to do some digging in the iso tank.
Day 29 - Fasty dug down into the moss and EE in his tank.
Day 51 - Fasty molted!
Day 58 - Fasty is up and exploring the iso tank, with new legs and claws.
Day 131 - Fasty came up from his second molt after the attack.
Day 223 - Fasty dug under for his third molt after the attack.
Day 242 - Fasty came up from his third molt!