Finland's exceptionally warm December has confused migratory birds on their way south for the winter and encouraged other birds to sing and mate as if it were spring, experts said on Friday.
"Some of them (migratory birds) did not even leave because early winter was so warm and probably some of them first went south and came back," Lauri Haenninen, spokesman for environmental group Birdlife Finland, told AFP.
Skylarks, starlings and lapwings that usually head to warmer and more southerly climbs have been most affected by the mild weather. "They should leave when the weather is colder," Haenninen said.
Blackbirds have started singing and ducks, also confused by the warm winter, are mating several months before they normally search for partners.
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http://www.terradaily.com/2006/061215162737.n4ybxqly.html