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Why We DON'T Dig Up Hermit Crabs!

It's an itch we all want to scratch right? When your crab has been down for what feels like forever and you start getting stressed thinking are they okay!?

Should I dig them up to make sure?

Trust me, we have ALL been there. Even the long time owners still stress when they haven't seen their crabs in a long time. It's normal to fret about something that we can't see, the unknown.

In this blog, we will delve into the reasons why you should never give into that itch, and if you REALLY want to dig something... grab a shovel and go dig in the backyard. Trust me!

Why is digging up a Hermit Crab a bad thing?

There are 3 reasons why your crab has dug down into the substrate, 1. They are moulting. 2. They are distressing. And 3. They are just having fun digging.

The problem here is, we don't actually know which one they are doing at the time when they go down. Are they digging, distressing, moulting? There's no way to know.

What we do know is that moulting is an extremely delicate and dangerous time for a hermit crab. During this time, they shed their exoskeleton and are left with a brand new, soft exoskeleton that is extremely susceptible to damage from yourself and other crabs. Not only are they now extremely delicate, but they are very weak and vulnerable. Moulting should always take place deep within the substrate, away from direct light and predators such as other Hermit Crabs.

When we dig up a crab that is moulting, we are disturbing an extremely intricate process that should never be disturbed.

The amount of issues that can arise from digging up a moulting crab include severe stress, limb loss, and most commonly, death.

Crabs who have been dug up during mid moult will become extremely stressed and will start to display signs of stress such as dropping their limbs (legs and claws literally falling off), leaving their shell to go naked, and dying.

I've already dug up a moulting crab, what now!?

Now you will need to follow the surface moulting procedures. You can find an in-depth blog on surface moulting here

The moulting crab must be placed into isolation immediately. A plastic container with a secure lid will do. Fill it with a small amount of substrate and place the moulting crab inside. If you have come across their shed exoskeleton, this needs to go into the isolation tub with them.

Cover the tub so they have darkness, and place the tub back into the main tank for heat and humidity.

Now all you can do is wait. Your crab may or may not survive this process. Surface moulting is never normal and is always an emergency that must be dealt with straight away.

Your crab cannot leave the isolation tub until they have consumed their shed exoskeleton, and their new exoskeleton has hardened up and they are walking around their iso tank.

Letting them back into the general population too early is a death sentence. They will be susceptible to attacks from the rest of the crew and it almost always leads to death.

My crab wasn't moulting when I dug it up, so it's okay right?

Nope. It's never okay. Just because your crab wasn't moulting, doesn't mean you haven't caused it a serious amount of stress. This can lead to them going naked or dropping limbs, and sometimes even death. Crabs don't handle stress very well, and unfortunately it doesn't take much to really stress them out.

But what if they are dead and I don't know, I need to dig them up to find out!

If you dig them up to find out if they are dead, you will either 1. Find a dead crab and you have achieved nothing. Or 2. Find a moulting crab and it's likelihood of dying has now tripled. So either way, you're heading down the path of a dead or injured crab by digging them up.

Is there ever a time when we SHOULD dig them up?

There are some extreme instances when you MUST dig up your Hermit Crabs, whether they are moulting or not. These include, flooding of the substrate, ant infestation, natural disasters such as bush fires, hurricanes, or moving house.

If you must dig them up for the above reasons, you should always dig very carefully and gently into the substrate until you find a moult cave. Never touch the crab! Gently use a container or spoon to pick the crab and any shed exoskeleton up and quickly place them into an isolation tub.

Your isolation tub should contain a small amount of substrate and nothing else. They don't need food and water during moulting. Yes it is always a risk digging up a moulting crab, but if you are experiencing a tank emergency, it is safer to dig them up then to let them die in the sub due to the emergency at hand.

How long is too long for them to stay down tho?

There is no right or wrong answer to this question. Some crabs can stay down for weeks, and some can stay down for months, even going on as long as a year!

Being nocturnal, your crabs may be coming up at night without you even knowing and then going back down during the day. The only real way to know is to install a camera in your tank to see if there is any night time activity.

If it has been an extremely long time, 1+ years and you haven't seen your crab, it's safe to assume that they have not survived.

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