Crab stowaways

[crabmom]

Hello. We went clamming in Bodega Bay and found some surprise tiny crabs hiding in the clams. They look like their baby rock crabs and maybe another type. Our friends that we went with used them for cat treats however my five-year-old would like to keep them alive until we can return them. There are three of them. They are the size of a dime. We kept them with the big bucket That had live clams but that is no more. We put them in a small terrarium with above ground structure and they seem to like to be underwater. I have to change it today or I don’t think they will live. What can I do to give them some water that they can tolerate and an environment that will work today? Temperature wise they are almost outside in our mudroom so that keeps them nice and cool.
Looking for help to get something to keep them happy today. thank you.

 

[SaltyT]

Welcome to R2R!

I believe those are a type of parasitic pea crab. I'm not sure that you'll be able to keep them alive very long outside of a clam. If you do manage to keep them alive you may not want to return them to the sea, parasitic crabs aren't good for a clam's health.