Cuckoos have declined by 65% in the UK since 1995. BTO satellite tagging research tracks individual cuckoos on their migration to Africa, revealing mortality hotspots across the Sahara and Sub-Saharan Africa that inform conservation action.
Satellite tagging involves live capture and attachment of a small backpack transmitter. Research protocols minimise handling stress, but the attachment represents an ongoing burden on individual birds. The welfare cost is considered justified by the conservation information gained, particularly identification of mortality hotspots that allow targeted conservation intervention. Individual tagged birds provide invaluable data on survival rates and migration phenology that benefits the entire declining population.