Not long after Chris left the swamp forests, Derek also left the area, travelling 230 km (144 miles) southwest to an area of the Cuvette region in central Congo.
Tracking Cuckoos to Africa... and back again
The 'Red Listed' Cuckoo is one of the UK's fastest declining migrants and, until recently, was one of which we knew least about once it left the UK.
In 2011 we attached satellite-tracking devices to Cuckoos from Norfolk to find out more about their important stop-over sites and wintering destinations on the way to and from Africa. Since then we have been able to expand the project thanks to support from funders and sponsors. Read more about the project and find out what we have learnt so far.
To return to this page in future, or to tell your friends, visit www.bto.org/cuckoos.