While defending a entire large scale broad acre grain property would not likely be economically viable other than defending bird hot spot areas. Other growers can make extensive use of a Bird Gard system.
Where Bird Gard comes into its own is with crops such as Rice, vegetables, peanuts, watermelons and high value seed crops etc.
The usual pest birds pest birds here are Crows, Ducks, Cockatoos, Galahs and Starlings. In New Zealand seed growers know all about Thrushes and finches.
In the above situations, the 360 degree surround sound devices such as Multi-Blaster, Super Pro X, Bird -X 1, Crop Gard and the most powerful of them all the "Pro Amp" are the devices most often used. They simply cover the entire area of crop under a blanket of protective sound.
Any grower with a nocturnal Duck or other water bird problem would do well with the Bird Gard Laser, which can be seen as a Non- Harmful, non-lethal replacement of the Shotgun.