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Cuckoo decline finally mapped

Forty-two tiny tracking devices fitted to cuckoos in the UK may have solved the mystery of the birds' decline.

Britain has lost more than 70% of its cuckoos in the past 25 years.

A study tracking their migration has now revealed that the birds have two migration routes - and one appears to be more risky than the other.

The findings are published in the journal Nature Communications.

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