UK now a winter destination for Mediterranean birds

Research from the BTO has revealed that the UK is now playing host to wintering Blackcaps from a surprisingly large range of countries.

Most birds that flock to UK shores in winter are leaving behind inhospitable conditions in Scandinavia and eastern Europe, rather than the balmy climes of the Mediterranean.

But the BTO's findings, made in conjunction with the University of Oxford and the Max Planck Institute in Munich, show that a significant proportion of the UK's wintering Blackcaps breed in the sort of places what British people might visit for a bit of winter sun.

Blackcaps historically migrated to the UK in spring from southern Europe and returned there after the breeding season. In recent years, more and more Blackcaps have been spending the winter in the UK, where they can often be found at garden feeders. The researchers found that Blackcaps are now travelling to Britain for the winter from countries as diverse as Spain in the west to Poland in the east.

Increasing numbers of Blackcaps are overwintering in the UK from breeding grounds as diverse as Spain and Poland (Stephen Pogson).

Over four years, volunteers fitted 600 Blackcaps wintering in the UK with unique colour combinations of easily identified leg rings, allowing researchers to track sightings of the birds as they returned to their breeding grounds. An additional 30 Blackcaps were fitted with tiny tracking devices that gave more detailed information about the birds' routes. 

Although the reasons for this northwards migration are not well understood, other work by BTO scientists suggests that warmer winter weather in the UK and widespread garden bird feeding may be helping these birds to survive.

Rob Jaques, BTO Garden BirdWatch Supporter Development Officer, said: "When these wintering Blackcaps first arrive in the UK, they feed in the wider countryside, only moving into gardens as the winter deepens. Our network of BTO Garden BirdWatchers – who keep a weekly record of the birds and other wildlife using their gardens – are well-placed to collect new information on these visiting birds, but we need to increase the number of gardens being covered, so that we can increase our understanding of this unexpected behaviour."