The Common Crane (Grus grus) is a sophisticated bird that can fly high and over long distances. It is a faithful migratory bird that flies the same routes and always stops at the same places. They return to the same wintering grounds every year. Cranes use thermal lift and fly between 200 and 1,500 m above sea level. During migration they sometimes fly at night to save their strength. At night the air is cooler, denser, and the winds are often more favourable. The cranes thus avoid hyperthermia and dehydration.