What behavior causes an animal to be inactive for a long peiod of time?

The behavior that causes an animal to be inactive for a long period of time is called torpor. Torpor is a state of reduced activity and metabolic rate that is often used by animals to conserve energy during periods of food scarcity or extreme weather conditions. It is also known as hibernation when it is done during the winter months, and estivation when it is done during the summer. During torpor, an animal's body temperature may drop significantly and it may appear to be asleep, however it can be easily aroused if necessary. Typically torpor bouts last from a few hours to several weeks, with longer periods of torpor being observed during hibernation.