Maybe this was it, although I thought it was more recent than 2003; from the Pittsburgh Post-Gazette online:
Friday, April 18, 2003
By Don Hopey, Post-Gazette Staff Writer
Boris, the founding father of Pittsburgh's peregrine falcon revival, is dead, decapitated near a nest box on a 37th-floor ledge of the Gulf Building where he had sired and helped raise 40 young since 1991.
His killing, most likely by a rival male falcon in a dispute over the nesting site, caps a tumultuous spring on the Downtown skyscraper, played out like a feathered "I, Claudius" episode, with two male and two female falcons coming and going and courting and returning and courting throughout the spring.
There have been at least two different egg clutches laid by two females, with another most likely on the way, the result of a union between Boris' female companion since 1998 and his killer.
Although no one saw the falcons fight to the death last Thursday night or Friday morning, that remains the most likely explanation for Boris' demise, said Charles Beir, the Western Pennsylvania Conservancy's natural heritage director. Another possibility could be a fight with a great horned owl, but Beir said that is less likely.
He said decapitation is instinctual for peregrine falcons. As part of their feeding behavior, falcons capture other birds -- some as large as a duck -- with their talons and snap their heads off using a special notch on the upper mandible of their beaks.
"I know of no other occurrence where a falcon has been decapitated," Beir said. "It could have happened in any mix. It just comes down to one bird having the advantage over another and overpowering it."
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The killing was not caught on tape.
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Beir said there has been competition for nesting sites in Detroit, Columbus and Pittsburgh. In Columbus last year, one female falcon killed another female but didn't decapitate it.
In the Oakland section of Pittsburgh, rival male falcons fought over the nesting site on the Cathedral of Learning.
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The public can follow the drama atop the Gulf Tower and also at the University of Pittsburgh nest site on the Cathedral of Learning on the Conservancy's Web site:
www.paconserve.org