Yes and no. Yes, because their shells are attached to their bodies(the shell is partly made up by the turtle's backbone), and if it were removed, the turtle would die. However, the turtles do not use their shells as shelter. There are several different habitats for turtles, depending on what type they are. For example, the snapping turtle and the painted turtle both like aquatic environments. The Box turtle likes a more dry environment, and the list goes on.
Apparently, if they are kept indoors in a warmer temperature over winter, they do not need to hibernate.
If a tortoise is unwell they shouldn't be hibernated. So no they don't HAVE to hibernate but if you want to keep their lives as natural as possible you should let them hibernate as long as they don't have any medical conditions. Research should be done before hibernation to establish what food requirements may be needed.
No, some turtles leave their head and tail out of the shell
They sleep in there shells.
inside water
They do not sleep underwater but when resting, it lies at the bottom, buried in sand or mud, lifting its head to breathe or snatch at prey.
turtles do not sleep
They either sleep on land or in the water.
well since sea turtles rarely sleep they really dont but if they do they will sleep on a nearby beach
they crawl into their shells and sleep
Turtles, like any other animal, sleep when they need to. I catch my four napping on a regular basis. They love catching a snooze while out sunning themselves. They can't sleep under water they have to be basking. If they were to sleep under water they might drown. My turtle spent her first night completely undewater (sleeping) So I guess they do sleep underwater they hold their breath for hours
red bellied turtles sleep on the moist hard rocky shore of fresh water
none
pet turtles can sleep as much as they want in water if they loose oxygen they will lift their heads and get oxygen
Its' shell.
they can sleep up to 15 hours