After the breeding season, Common Cranes (Grus grus) in northern Europe gather in sometimes large numbers to migrate south to winter in warmer areas. These are powerful birds capable of travelling up to 1,553 miles (2,500 km) before reaching their destination. They spend the winter in North Africa or in southern Europe (south of Spain). Since the 2000s, due to global warming, some of the birds have been wintering in France, such as on the Lac du Der-Chantecoq. In flight, Common Cranes scream every ten to fifteen seconds.