Sparrows and Starlings are smaller birds which are harder to control with traditional bird control methods. They become even more difficult to control is they are nesting. Populations of small birds such as these can become extremely large, if left unattended with no specific bird control solution in place.
Bird nests should be removed prior to using any BirdStopper's products. If birds are in trees, and nests cannot be physically removed, products need to be in the trees with the birds in order to have any desired effect!
Electronic products typically do not work immediately! Actually, in some cases, the electronics DO produce immediate and dramatic results.