The Truth About Gazing Balls

I love gazing balls, but I've heard they can confuse birds. Is this true?

—Bonnie Parton, Denham Spring, Louisiana

George: The problem with gazing balls is that birds can see their reflections in them. During the breeding season, the reflections appear to be another bird that has invaded the territory. As a result, the real bird will fight the reflection in an attempt to chase it away. This behavior can go on for weeks.