ROME -- Giovanni Albarella won't back down from a street fight, even though he's always outnumbered.

As the sun goes down, Mr. Albarella often squares off against millions of birds that cloud the skies of this ancient city.

European starlings -- birds individually small enough to fit in a hand -- are collectively a menace. They swoop and poop indiscriminately, clearing Rome's outdoor cafes, frightening children and, more recently, forcing an emergency landing of a Boeing 737.

Mr. Albarella says he has a method to shoo the birds away. Backed by city hall, the 37-year-old conservationist and a team of assistants criss-cross Rome with high-powered megaphones that they point at trees teeming with starlings. The goal: to drive the birds out of the city and back to the countryside.

The megaphones emit what Mr. Albarella calls a "heart-rending scream" -- a recording of starlings issuing a screeching distress call.

The sound, he says, is the only way to drive the birds from their roosts without harm.

"This is a great responsibility," Mr. Albarella says, as the flocks began filtering into town one recent evening. "You delve into a conflict, a tension, a problem of cohabitation between man and animal."

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