Why has my hermit crab buried himself??!!

I live in West Virginia, and my hermits want to bury themselves for long periods of time, and I really think it has to do with the temperature and season change. Do you give your hermits regular baths? I will make sure that my bathroom sink is clean and put a large natural sponge in the sink (wet the sponge), and then give them a bath. After their bath, I leave them in the sink for awhile for exercise. The bath energizes them, and they will crawl all over the sponge for quite a while. I shut the bathroom door so our cat won't try to play with them. They interest her, and I know she doesn't want to harm them, but she'll bat them around. My husband knows that if the bathroom door is shut that we have crabs in the sink or Drano in the tub! :)

hmm, no i've done a head count and they're all there except for moggil. It's so sad seeing his empty shell every day, i have no idea what happened to him. I don't take them out and give them a bath but there is a tub of salt water in their tank. I know they use it because it regularly gets full of sand. I like your method of bathing them though- I will start doing that once a week. Thanks for your replies!

I'm sorry to hear that you can't find one of your hermits! The only other possible explanation I can think of is that he left his shell and managed to get out of the tank and run off. Sometimes when crabs get sick they will abandon their shell, and some do try to get away. It must be a natural instinct for animals in general. Have you looked around the tank and on the floor to see if he has made it so far before he might have passed away. Again, I hate to hear that he's gone. Did you do a complete tank cleaning? Oh, and the baths...I usually just get the water around room temp and run them under the small stream of water for probably fifteen to thirty seconds. I'll even tip them upside down and let it run in their shells, but then I hold them above the sink, right side over, and let them drip dry for fifteen to thirty seconds so the water doesn't just sit in their shells. The baths really get them active!