Males do it to attract a mate.
With pollution in the air it makes it hard for them to find food and good homes/burrows!
You can tell a land hermit crab from a water hermit crab by looking at the claws/arms or legs. If it is a water crab it will be blueish and if land crab it will be pinkish purpleish. If your crab is a water crab don't just throw it in water and leave it there, put a tiny bowl in it's tank or cage that is low to the ground and make sure that the water level is a bit lower than the hermit crabs top of its legs. Also have a wet sponge for each kind of hermit crab in the crabs tank.
They would have to sleep in water because the can spend one hour on land.
There are crabs which breathe water and crabs which breathe air. It is rare to find a crab that does both but intertidal crabs do but they must remain wet to breath air (strange, right?).
Land crabs (most pets are) do need it while marine crabs like the ones you find at the beach do not.
no
Yeas they do.
oxygen (air) and water
Crabs raise one of their larger claws, often referred to as a "major claw," as a display of dominance and to signal their readiness to defend themselves or establish territory. This behavior can also be a part of mating rituals, where the raised claw attracts potential mates. Additionally, the raised claw helps in communication with other crabs, conveying aggression or submission depending on the context.
Absolutely. Everything that breathes air has lungs.
No they dont have air fresheners for hermit crabs
They extract oxigen (O) out of water (H2O) when in water or simlpy out of the air when in open air.