Birds on the Move
Why should a wheatear double its weight before migration, while a swallow retains its slim figure? Why do some birds make their journey in marathon flights and others by easy stages, some by day and some by night? At an observatory on the east coast of Lincolnshire, we consider the different ways in which birds accomplish the regular miracle of migration. Producer DILYS BREESE (Bristol) (Repeated: Wednesday 9.5 am)