Migratory birds which travel thousands of miles to Africa each winter have seen populations tumble in the last few decades, conservationists have warned.

The latest annual assessment of UK birds has revealed that species which nest in the UK in summer and migrate for winter in Africa’s tropical forests have seen the worst declines, the latest annual State of the UK’s Birds report showed.

Those species that winter in the ‘humid zone’ stretching from Senegal to Nigeria and beyond, which include birds such as the nightingale, tree pipit and spotted flycatcher, have seen numbers drop by just over 70 per cent as a group since the late 1980s.

Species which winter in Africa’s ‘arid zone’ just south of the Sahara Desert, including sand martins, whitethroats and sedge warblers, have not fared as badly. The report showed their numbers had fluctuated considerably since 1970, but had seen a decline of less than 20 per cent overall.

The turtle dove has suffered population falls of 88 per cent since 1995

It is the first time the State of the UK’s Birds has looked at population trends for 29 migratory species which nest in the UK in summer and migrate to the Mediterranean or sub-Saharan Africa, based on where they spend the winter months. The report, which is a collaboration between eight conservation groups and government agencies, also warned that some individual migratory species had seen dramatic declines.

The turtle dove, a traditional symbol of love and fidelity, which the report classifies as a species which winters in the humid zone, has suffered population falls of 88 per cent since 1995. Other species which spend the winter in the humid zone have also seen major declines in the same period, including the wood warbler, whose numbers fell two-thirds, and the pied flycatcher whose population more than halved (53 per cent).

Another UK favourite the cuckoo, which also spends winter months in the humid zone, has seen numbers almost halve (49 per cent) in under two decades.