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4/5 The summer's scattering of rooks is over and their communal urges bring them together.
3/5 As summer warmth dries out the earth, the young rooks have a hard time finding enough food
2/5 Some rookeries date back hundreds of years. Why are birds so loyal to one site?
1/5 At dusk, 40,000 rooks gather in the Yare Valley in Norfolk.