I use Water Wigglers in all of my birdbaths. These battery-powered gizmos agitate the water which attracts birds, and that moving water also discourages mosquitoes from laying their eggs.
My Water Wigglers have an evil aggressor, however. In the mornings, I often find them lying upside down in the birdbath. The spinner is always missing, and I have to go on a scavenger hunt to find it in the lawn.
I don’t think squirrels are flipping the Water Wigglers because I see squirrels drinking from my birdbaths all the time. The enemy always appears at night. That leads to me conclude that the culprits are raccoons, and my guess is that the little rattling noise from the spinner drives them stark raving mad.
If I were a bazillionaire I would place Water Wigglers all over my yard just to mess with their heads.