What are the sleeping posture of parrots

There are generally three pose for parrots to sleep.The first is the sleeping position, which is lying on the stand stick. It looks like being incubated. It usually has this posture when recovering physical strength and restraint.The second is to stand on one foot, and the body will be a little bit.The third type is to sleep in the hiding head and bury your head into the wings. This situation shows that it may be sick and need to be treated in time.