Ah, there's nothing quite like the harbingers of spring: mercury rising, flowers blooming, birds singing the dulcet tones of ... "Dixieland"?

It seems nature is heeding Nokia's call. Some of our feathered friends are adding mobile-phone ring tones to their repertoire. "You don't believe it the first time you hear it," says Nicolaj Nielsen, a business analyst at Denmark-based Strand Consult, who has witnessed birds mimicking mobile phones. "It's quite funny."

But it's not surprising, says Andrew South of the United Kingdom-based Royal Society for the Protection of Birds, who's heard similar reports. He points out that starlings are well-known mimics, borrowing about 10% of their songs from other sounds, such as doorbells and police sirens. Besides, they have a proven penchant for telephones. When touch-tone phones began replacing rotary phones in the United Kingdom, many starlings imitated the distinctive warbling tone. "They're just catching up with modern technology," South says.

There's no environmental impact associated with this phenomenon, he says--other than the frustration that might arise when someone lunges for a phone and finds the caller perched in a tree. Still, there's the threat of noise pollution, as phone users increasingly download snippets of pop music for ring tones. What if birds develop an affinity for, say, Britney Spears? South has a solution: "Then they should be shot."