[NAEP] Balmy winter puts chill on bird migration

[Dawn Wiseman]

Balmy winter puts chill on bird migration 
http://edition.cnn.com/2006/TECH/science/12/20/birds.migration.reut/index.html

Some European birds have failed to fly south for the winter, 
apparently lured to stay by weeks of mild weather that experts widely 
link to global warming.

Birds including robins, thrushes and ducks that would normally fly 
south from Scandinavia, for instance, have been seen in December -- 
long after snow usually drives them south. And Siberian swans have 
been late reaching western Europe.

"With increasing warmth in winter we suspect that some types of birds 
won't bother to migrate at all," said Grahame Madge, spokesman of the 
British Royal Society for the Protection of Birds (RSPB).

Many individual birds were leaving later, and flying less far.

One Swiss study this month suggested that Europe has just had the 
warmest autumn in 500 years. Frosts have crept south in the past week 
-- chilling any birds gambling that the entire winter will be balmy.