It is very easy to see trails of hermit crabs anywhere on the soft sand along the beach. In fact, I thought that the trails were decorations left by the hermit crabs! With my 100mm f2.8L macro on 5D II, I picked up one hermit crab and started adjusting the focus of my lens for some shots of it. The hermit crab went into hiding whenever my hand gets near it and that made it easier for me to frame my shots. All I have to do is pick up the hermit crab and place it carefully in my frame and waited for it to emerge from its hiding. It took split seconds to run for safety and I will have to carefully grab it back to the position I want.
Initially, it took a little longer to notice that it is safe to come out of its shell, after few shots, I have to be quick because it has already recognized the place and ready to run for safety once my hand left its shell. For the shot below, I caught a shot of it trying to run away from the spot. After I got the shots that I wanted, I put it back to the sea. No hermit crab was harmed in the process.