Many of our birds are pretty much resident, but some regularly migrate huge distances. These maps show where birds ringed in Britain and Ireland have been found since ringing began in 1909. The darker colours on the first map show where most birds have been found. The second shows the locations of all birds, with some of the most exceptional movements highlighted.
One bird, twelve journeys, 60 000 miles and invaluable scientific data: PJ the Cuckoo has left an incredible legacy.