Instructions
Place silhouettes of birds around the garage that mimic the natural predator of the species you wish to deter from entering. You can purchase these at an agricultural center or a hardware store.
Set up bird alarms in the garage. These can be audible, silent or ultrasonic, and may also include additional features to visually repel the bird from flying into the garage.
Apply a non-toxic deterrent to the building and any turf surrounding the garage. This is especially effective for birds such as Canada geese and starlings.
Add a bird slide or bird slope to any ledges on which the birds are nesting. The lack of anywhere to perch makes flying into the garage less desirable to the birds.
Install a low-voltage shock system that will not be lethal to the birds, but will act as a strong deterrent. Ensure that signs warning other people about the system are clearly visible.