As part of the BTO research programme in to Cuckoo migration, four Ceredigion cuckoos have been fitted with satellite trackers this year. The following link to an article in the Independent newspaper describes the programme in an excellent article by their nature correspondent.
http://www.independent.co.uk/environment/nature/nature_studies/nature-studies-by-michael-mccarthy-good-luck-indy--the-cuckoo-thats-carrying-our-name-to-africa-7869904.html
Further information on this fascinating programme is available from the links on the BTO website
www.bto.org/cuckoos