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Cuckoo migration 'now more perilous'

Britain has lost more than 70 percent of its cuckoos in the last 25 years, but tiny tracking devices fitted to some of the birds may have solved the mystery of their decline.

A study following their migration has revealed that cuckoos have two migration routes, with one that appears to be more risky than the other.

Victoria Gill reports.

  • 20 Jul 2016
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