Global warning may be affecting the migratory habits of some European songbirds.

Bird watchers say some birds are deviating from their annual winter flights to Africa, instead flying to Britain, National Geographic News reported Wednesday.

The data, from an ongoing survey of bird-watchers across Britain, indicates a number of birds who spend their summer in northern Europe are no longer migrating to Africa and the Mediterranean each fall.

"I am amazed by the numbers of warblers that were reported," Greg Conway, a researcher with the British Trust for Ornithology, which runs the survey, told National Geographic News. "It's as if the birds are now saying, 'Let's not bother to go all the way to Africa this winter,'" he said.

Scientists say the birds' migration to Britain instead of Africa could be a response to global warming. Increasingly mild winters mean the birds can now cope with Europe's coldest months, giving them a head start the following breeding season, NGN reported.

Copyright 2005 by United Press International