Birds Won't Use Bath

Help! I've had two white plastic birdbaths in my yard for years and have never seen a bird use them. I've changed locations and put a few flat rocks in them for birds to perch on. What am I doing wrong?

—Shelia Saxton, Gallipolis Ferry, West Virginia

George: Try locating the birdbaths closer to a shrub or other natural cover that will provide an escape for the birds if they feel threatened. Also, the water may be difficult for birds to see in the white baths. Try painting them an earth color to make the water more visible.