Moving water attracts birds like crazy. The Water Wiggler does this and at the same time prevents mosquitos that may carry West Nile Virus from laying eggs in your birdbath. Creates ripples in the water to entice birds and deter mosquitos. No electric hook up and very silent. Runs on two D batteries which will run it for a full season of continuous use, 24 hours a day. Batteries not included. Can even be used in a heated bath. One year warranty.